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The services required for a PM program are generally non-corrective procedures. However, often while performing PM on a vehicle, a technician notices the need for a minor repair. Both PM and those basic minor services are covered in the rest of this section. +++6 Fender covers should be used when working under the hood. Customer Care: Whenever you do any service to a vehicle, use fender covers and don’t leave fingerprints on the exterior or interior of the car. If oil or grease gets on the car, clean it off. === TABLE 1 ENGINE OIL SERVICE RATINGS RATING | COMMENTS SA Straight mineral oil (no additives), not suitable for use in any engine SB Non-detergent oil with additives to control wear and oil oxidation SC Obsolete since 1964 SD Obsolete since 1968 SE Obsolete since 1972 SF Obsolete since 1980 SG Obsolete since 1988 SH Obsolete since 1993 SJ Obsolete since 1997 SL Started in 2001 SM Started in 2005 === Engine Oil: Engine oil is a clean or refined form of crude oil. Crude oil, when taken out of the ground, is dirty and does not work well as a lubricant for engines. Crude oil must be refined to meet industry standards. Engine oil (often called motor oil) is just one of the many products that come from crude oil. Engine oil is specially formulated so that it: ¦ Can flow easily through the engine ¦ Provides lubrication without foaming ¦ Reduces friction and wear ¦ Prevents the formation of rust and corrosion ¦ Cools the engine parts it flows over ¦ Keeps internal engine parts clean Engine oil contains many additives, each intended to improve the effectiveness of the oil. The American Petroleum Institute (API) classifies engine oil as standard or S-class for passenger cars and light trucks and as commercial or C-class for heavy-duty commercial applications. The various types of oil within each class are further rated according to their ability to meet the engine manufacturers' warranty specifications. Engine oils can be classified as energy-conserving (fuel-saving) oils. These are designed to reduce friction, which in turn reduces fuel consumption. Friction modifiers and other additives are used to achieve this. In addition to the API rating, oil viscosity is important in selecting engine oil. The ability of oil to resist flowing is its viscosity. The thicker the oil, the higher its viscosity rating. Viscosity is affected by temperature; hot oil flows faster than cold oil. Oil flow is important to the life of an engine. Because an engine operates under a wide range of temperatures, selecting the correct viscosity is very important. The Society of Automotive Engineers (SAE) has established an oil viscosity classification system that is accepted throughout the industry. This system is a numeric rating in which the higher viscosity, or heavier weight, oils receive the higher numbers. For example, oil classified as SAE 50 weight oil is heavier and flows slower than SAE 10 weight oil. Heavyweight oils are best suited for use in high-temperature regions. Low-weight oils work best in low-temperature operations. Although single viscosity oils are available, most engine oils are multi-viscosity oils. These oils carry a combined classification such as 10W-30. This rating says the oil has the viscosity of both a 10- and a 30-weight oil. The "W" after the 10 notes that the oil's viscosity was tested at 0°F (-18°C). This is commonly referred to as the "winter grade." Therefore, the 10W means the oil has a viscosity of 10 when cold. The 30 rating is the hot rating. This rating was the result of testing the oil's viscosity at 212°F (100°C). To formulate multiviscosity oils, polymers are blended into the oil. Polymers expand when heated. With the polymers, the oil maintains its viscosity to the point where it’s equal to 30-weight oil. The SAE classification and the API rating are displayed on the container of oil ( +++7). ISLAC Oil Ratings: The International Lubrication Standardization and Approval Committee (ISLAC) has developed an oil rating that combines SAE viscosity ratings and the API service rating. If engine oil meets the standards, a "sunburst" symbol is displayed on the container ( +++8). This means the oil is suitable for use in nearly any gasoline engine. SHOP TIPS Many engines have very specific requirements. Always install the type of oil specified by the manufacturer. Never assume that a particular type of oil can be used in an engine. Synthetic Oils--Synthetic oils are considered synthetic because the finished product does not occur naturally and it was made through a chemical, not natural, process. The introduction of synthetic oils dates back to World War II. Synthetic oils have many advantages over mineral oils, including better fuel economy and engine efficiency by reducing friction; they have low viscosity in low temperatures and a higher viscosity in warm temperatures, and they tend to have a longer useful life. Synthetic oils cost much more than mineral oils, which is the biggest draw back for using them. Engine oils that are blends of mineral oils and synthetics to keep the cost down are available but offer many of the advantages of synthetic oil. Maintenance--Perhaps the PM service that is best known to the public is changing the engine's oil and filter. Because oil is the lifeblood of an engine, it’s critical that the oil and filter are changed on a regular basis. Photo Sequence 3 shows the steps involved in changing the engine oil and oil filter. Whenever doing this, make sure the oil is the correct rating for the vehicle. In between oil and filter changes, the level of the oil should be periodically checked. When doing this, make sure the vehicle is parked on level ground. Locate and remove the oil dipstick. With a clean rag, wipe the oil from the dipstick and reinsert it all the way in its tube. Remove it again and check the level of the oil ( +++9). If the level is at the "full" mark, the level is okay. If the level is at the "add" mark, this means the level is about 1 quart low. Regardless of the level, examine the oil for evidence of dirt. If the oil is contaminated, it must be changed. API SERVICE SM SAE 5W-30 ENERGY CONSERVING ECONOMIZE; L; ENERGIZE +++ The SAE classification and the API rating are displayed in this way on a container of oil. • AMERICAN PETROLEUM INSTITUTE • FOR GASOLINE ENGINES C E R T I F I E D +++ The ILSAC certification mark, commonly referred to as "the Starburst." +++Check the engine's oil level with the dipstick. ------- Changing the Oil and Oil Filter: P3-1 Always make sure the vehicle is positioned safely on a lift or supported by jack stands before working under it. Before raising the vehicle, allow the engine to run awhile. After it’s warm, turn off the engine. P3-2 The tools and other items needed to change the engine's oil and oil filter are rags, a funnel, an oil filter wrench, safety glasses, and a wrench for the drain plug. P3-3 Place the oil drain pan under the drain plug before beginning to drain the oil. P3-4 Loosen the drain plug with the appropriate wrench. After the drain plug is loosened, quickly remove it so the oil can freely drain from the oil pan. P3-5 Make sure the drain pan is positioned so it can catch all of the oil. P3-6 While the oil is draining, use an oil filter wrench to loosen and remove the oil filter. P3-7 Make sure the oil filter seal came off with the filter. Then place the filter into the drain pan so it can drain. After it has completely drained, discard P3-8 Wipe off the oil filter sealing area on the engine block. Then apply a coat of clean engine oil onto the new filter's seal. P3-9 Install the new filter and hand tighten it. Oil filters should be tightened according to the directions given on the filter. P3-11 Tighten the drain plug according to the manufacturer's recommendations. Overtightening can cause thread damage, whereas undertightening can cause an oil leak. P3-12 With the oil filter and drain plug installed, lower the vehicle and remove the oil filler cap. P3-10 Prior to installing the drain plug, wipe off its threads and sealing surface with a clean rag. P3-13 Carefully pour the oil into the engine. The use of a funnel usually keeps oil from spilling on the engine. P3-14 After the recommended amount of oil has been put in the engine, check the oil level. P3-15 Start the engine and allow it to reach normal operating temperature. While the engine is running, check the engine for oil leaks, especially around the oil filter and drain plug. If there is a leak, shut down the engine and correct the problem. P3-16 After the engine has been turned off, recheck the oil level and correct it as necessary. ------- Cooling System: Whenever you change an engine's oil, you should also do a visual inspection of the different systems under the hood, including the cooling system. Inspect all cooling system hoses for signs of leakage and/or damage. Replace all hoses that are swollen, cracked, or show signs of leakage. The radiator should also be checked for signs of leaks; if any are evident the radiator should be repaired or replaced. Also, check the front of the radiator for any buildup of dirt and bugs ( +++10). This can restrict airflow through the radiator and should be removed by thorough cleaning. The level and condition of the engine's coolant should also be checked. Check the coolant's level at the coolant recovery tank ( +++11). It should be between the "low" and "full" lines. If the level is too low, more coolant should be added through the cap of the tank, not the radiator. Bring the level up to the "full" line. Always use the correct type of coolant when topping off or replacing it. Look at the color of the coolant when checking the level. It should be green, or perhaps orange, but it should not look rusty or cloudy. If the coolant looks contaminated, the cooling system should be flushed and new cool ant put into the system. SHOP TIPS Recycle all used antifreeze/coolant or take it to an authorized collection point. Don’t dump old coolant into a sewage drain, the ground, or any body of water. CAUTION! Never remove the radiator cap when the coolant is hot. Because the system is pressurized, the coolant can be hotter than boiling water and will cause severe burns. Wait until the top radiator hose is not too hot to touch. Then press down on the cap and slowly turn it until it hits the first stop. Now slowly let go of the cap. If there is any built-up pressure in the system, it will be released when the cap is let up. After all pressure has been exhausted, turn the radiator cap to remove it. Coolant Engine coolant is a mixture of water and antifreeze/coolant. Water alone has a boiling point of 212°F (100°C) and a freezing point of 32°F (0°C) at sea level. A mixture of 67% antifreeze and 33% water will raise the boiling point of the mixture to 235°F (113°C) and lower the freezing point to _92°F (_69°C). As can be seen in +++12, antifreeze in excess of 67% will actually raise the freezing point of the mixture. Normally, the recommended mixture is a 50/50 solution of water and antifreeze/coolant. Some coolant suppliers offer a mixture of pure water and antifreeze that can be used to top off a cooling system when the level is low ( +++13). +++10 A buildup of dirt and bugs can restrict airflow through the radiator. +++11 The level of coolant in the cooling sys tem should be checked at the coolant recovery tank.
FREEZING BOILING ANTIFREEZE / COOLANT +++ The relationship of the percentage of antifreeze in the coolant to the coolant's freezing and boiling points. +++13 Topping off the cooling system with a 50/50 mixture of antifreeze and water. +++Ethylene glycol is the most commonly used antifreeze/coolant and is green in color. OAT coolant is orange and is often referred to by a brand name "DEX-COOL." +++ A refractometer that tests coolant condition and battery electrolyte. Viewpoint illuminator; Optical wedge; Lens Prism; Reticle scale; Lenses; Eyepiece; Sample area +++Measuring antifreeze and battery electrolyte levels with a refractometer. 1. Place a few drops of the sample fluid on the measuring prism and close the cover. 2. Hold up to a light and read the scale. The antifreeze concentration must always be a minimum of 44% all year and in all climates. If the percentage is lower than 44%, engine parts may be eroded by cavitation, and cooling system components may be severely damaged by corrosion. Five types of coolant are commonly available: ¦ Ethylene glycol-This is the most commonly used antifreeze/coolant. It’s green in color and pro vides good protection regardless of climate, but it’s poisonous. CAUTION! Never leave ethylene glycol or propylene glycol coolant out and lying around. Both children and animals will drink it because of its sweet taste. The coolant is poisonous and can cause death. ¦ Propylene glycol-This type has the same basic characteristics as ethylene glycol-based coolant but is not sweet tasting and is less harmful to animals and children. Propylene glycol-based coolants should not be mixed with ethylene glycol. ¦ Phosphate-free-This is ethylene glycol-based coolant that has no phosphates, which makes it more environmentally friendly. Phosphate free coolant is recommended by some auto manufacturers. ¦ Organic acid technology (OAT)-This coolant is also environmentally friendly and contains zero phosphates or silicones. This orange coolant is often referred to by a brand name "DEX-COOL" and is used in all late-model GM vehicles ( +++14). ¦ Hybrid organic acid technology (HOAT)-This is similar to OAT coolant but has been enhanced with additives that make the coolant less abrasive to water pumps. Coolant Condition A coolant hydrometer is used to check the amount of antifreeze in the coolant. This tester contains a pickup hose, coolant reservoir, and squeeze bulb. The pickup hose is placed in the radiator coolant. When the squeeze bulb is squeezed and released, coolant is drawn into the reservoir. As coolant enters the reservoir, a pivoted float moves upward with the coolant level. A pointer on the float indicates the freezing point of the coolant on a scale located on the reservoir housing. A refractometer offers a precise way to check coolant condition. Most refractometers can also measure the specific gravity of battery electrolyte and test the condition of brake fluid. A sample of the fluid is placed in the sample area of the meter and as light passes through the sample, a line is cast on the meter's scale. The line shows the concentration of the antifreeze in the coolant. Test strips are also used to gain a precise evaluation of coolant. The test strips are immersed into a sample of coolant. After about 5 minutes the strip will change color. The color of the strip is then compared to a scale on the container of strips. Matching the colors will indicate the freeze protection level and the acidity of the coolant. Drive Belts: Drive belts have been used for many years. V-belts and V-ribbed (serpentine) belts are used to drive water pumps, power steering pumps, air-conditioning compressors, generators, and emission control pumps. Heat has adverse effects on drive belts and they tend to overcure due to excessive heat. This causes the rubber to harden and crack. Excessive heat normally comes from slippage. Slippage can be caused by improper belt tension or oily conditions. When there is slippage, heat also travels through the drive pulley and down the shaft to the support bearing of the component it’s driving. These bearings may be damaged if the slippage is allowed to continue. V-belts ride in a matching groove in the engine's pulleys. The angled sides of the belt contact the inside of the pulleys' grooves ( +++19). This point of contact is where motion is transferred. As a V-belt wears, it begins to ride deeper in the groove. This reduces its tension and promotes slippage. Because this is a normal occurrence, periodic adjustment of belt tension is necessary. Drive belts can be used to drive a single part or a combination of parts. An engine can have three or more V-belts. In some cases, two matched belts are used on the same pulley set. This increases the strength of the belt and pulley connection and pro vides redundancy in case a belt breaks. Most late-model vehicles use a serpentine belt to drive all or most accessories. Serpentine belts are long and follow a complex path that weaves around the various pulleys ( +++20). Proper tension is critical on a serpentine belt due to the complex routing. Serpentine belts are flat on the outside and have a series of continuous ribs on the inside. These ribs fit into matching grooves in the pulleys. Both the ribbed side and the flat side of the belt can be used to transfer power. Over time, the belts will stretch and lose their tension. To compensate for this and to keep a proper amount of belt tension, most serpentine belt systems have a belt tensioner pulley. This pulley is a spring loaded pulley ( +++21) that exerts a predetermined amount of the pressure on the belt to keep it at the desired tension. +++18 A V-belt rides in a single groove, whereas a V-ribbed belt rides in several grooves. V-belt V-ribbed belt Cordline below top of pulley groove Belt off at bottom of groove Pulley groove +++19 The sides of a V-belt contact the grooves of the pulleys. +++20 A serpentine drive belt. +++17 Matching the color of a test strip to the scale on its container will indicate the freeze protection level and the acidity of the coolant. +++21 A belt tensioner for a serpentine belt. +++22 Drive belts should be inspected. Cracked Oil-soaked; Glazed Torn or split +++23 Check the tension of a drive belt with a belt tension gauge. If a belt does not have the proper tension, it may squeal or chirp, it may roll off a pulley, or it may slip. Excessive tension may put unwanted forces on the pulleys and the shafts they are attached to, leading to noise, belt breakage, glazing, and damage to the bearings and bushings in the driven components. Inspection Even the best drive belts last only an aver age of 4 years. That time can be shortened by several things; most of these can be found by inspecting the belts. Check the condition of all of the drive belts on the engine. Carefully look to see if they have worn or glazed edges, tears, splits, and signs of oil soaking. If these conditions exist, the belt should be replaced. Also inspect the grooves of the drive pulleys for rust, oil, wear, and other damage. If a pulley is dam aged, it should be replaced. Rust, dirt, and oil should be cleaned off the pulley before installing a new belt. Misalignment of the pulleys reduces the belt's ser vice life and brings about rapid pulley wear, which causes thrown belts and noise. Undesirable side or end thrust loads can also be imposed on pulley or pump shaft bearings. Check alignment with a straight edge. Pulleys should be in alignment within 1/16 inch (1.59 mm) per foot of the distance across the face of the pulleys. Belt Tension A quick check of a belt's tension can be made by locating the longest span of the belt between two pulleys. With the engine off, press on the belt midway through that distance. If the belt moves more than ½ inch per foot of free span, the belt should be adjusted. Keep in mind that different belts require different tensions. The belt's tension should be checked with a belt tension gauge. The tension should meet the manufacturer's specifications. Many engines are now equipped with a ribbed V-belt, which has an automatic tensioning pulley; therefore, a tension adjustment is not required. USING SERVICE INFORMATION: Proper belt tightening procedures and specifications are given in the specification section of most service manuals. The exact procedure for adjusting belt tension depends on what the belt is driving. Normally, the mounting bracket for the component driven by the belt and/or its tension adjusting bolt is loosened. The mounting brackets on generators, power steering pumps, and air compressors are designed to be adjustable. Some brackets have a hole or slot to allow the use of a prybar. Other brackets have a ½-inch square opening in which a breaker bar can be installed to move the component and tighten the belt. Other engines have an adjusting bolt, sometimes called a jackscrew, that can be tightened to correct the belt tension. Loosen the mounting bolts and hold the component in the position that provides for the correct tension. Be careful not to damage the part you are prying against. Then tighten the mounting bolts or tension adjusting bolt to keep the tension on the belt. Once tightened, recheck the belt tension with the tension gauge. Belt Replacement If a drive belt is damaged, it should be replaced. If there is more than one drive belt, all should be replaced even if only one is bad. Always use an exact replacement belt. The size of a new belt is typically given, along with the part number, on the belt container. You can verify that the new belt is a replacement for the old one by physically comparing the two. This, however, does not account for any belt stretch that may have occurred. Therefore, only use this comparison as verification. The best way to select the correct replacement belt is with a parts catalog and/or by matching the numbers on the old belt to the numbers on the new belt. To replace a V-belt on some engines, it may be necessary to remove the fan, fan pulley, and other accessory drive belts to gain access to belts needing replacement. Also, before removing the old drive belt, disconnect the electric cooling fan at the radiator, if the vehicle has one. Remove the old belt by loosening the components that have adjusting slots for belt tension. Then slip the old belt off. Check the condition and alignment of the pulleys. Correct any problems before installing the new belt. Place the new belt around the pulleys. Once in place, loosely tighten the bolts that were loosened during belt removal. Then adjust the tension of the belt and retighten all mounting hardware. SHOP TIPS -- It’s never advisable to pry a belt onto a pulley. Obtain enough slack so the belt can be slipped on without damaging either the V-belts or a pulley. Some power steering pumps have a ½-inch drive socket to aid in adjusting belts to the proper tension without prying against any accessory. +++The size and part number of a new belt are given on the belt container. The size can be verified by physically comparing the old with the new belt. Photo Sequence 4 shows the correct procedure for inspecting, removing, replacing, and adjusting a V-ribbed belt. Before removing a serpentine belt, locate a belt routing diagram in a service manual or on an underhood decal. Compare the diagram with the routing of the old belt. If the actual routing is different from the diagram, draw the existing routing on a piece of paper. After installation of a new belt, the engine should be run for 10 to 15 minutes to allow belts to seat and reach their initial stretch condition. Modern steel strengthened V-belts don’t stretch much after the initial run-in, but it’s often recommended that the tension of the belt be rechecked after 5,000 miles (8,000 km). +++A dirty and a clean air filter. ---------- Typical Procedure for Inspecting, Removing, Replacing, and Adjusting a Drive Belt P4-1 Inspect the belt by looking at both sides. P4-2 Look for signs of glazing. P4-3 Look for signs of tearing or cracking. P4-4 To replace a worn belt, locate the tensioner or generator pulley. P4-5 Loosen the hold-down fastener for the tensioner or generator pulley. P4-6 Pry the tensioner or generator pulley inward to release the belt tension and remove the belt. P4-7 Match the old belt up for size with the new replacement belt. P4-8 Observe the belt routing diagram in the engine compartment. P4-9 Install the new belt over each of the drive pulleys. Often the manufacturer recommends a sequence for feeding the belt around the pulleys. P4-10 Pry out the tensioner or generator pulley to put tension on the belt. P4-11 Install the belt squarely in the grooves of each pulley. P4-12 Measure the belt deflection in its longest span. If a belt tension gauge is available, use it and compare the tension to specifications. P4-13 Pry the tensioner or generator pulley to adjust the belt to specifications. P4-14 Tighten the tensioner or generator pulley fastener. P4-15 Start the engine and check the belt for proper operation. ----------- Air Filters: If an air filter is doing its job, it will get dirty. This is why filters are made of pleated paper. The paper is pleated to increase the filtering area. By increasing the area, the amount of time it will take for dirt to plug the filter becomes longer. As a filter gets dirty, the amount of air that can flow through it’s reduced. This is not a problem until less air than what the engine needs can get through the filter. Without the proper amount of air, the engine won’t be able to produce the power it should; nor will it be as fuel efficient as it should be. Included in the PM plan for all vehicles is the periodic replacement of the air filter. This mileage or time interval is based on normal vehicle operation. If the vehicle is used, or has been used, in heavy dust, the life of the filter is shorter. Always use a replacement filter that is the same size and shape as the original. An air filter should be periodically checked for excessive dirt or blockage. The best way to do this is to remove it and hold it up against a light. If little or no light passes through the filter, it should be replaced. Air filters are typically replaced every 30,000 miles (50,000 km). When replacing the filter element, carefully remove all dirt from the inside of the housing. Large pieces or dirt and stones accumulate here. It would be disastrous if that dirt got into the cylinders. Also make sure that the air cleaner housing is properly aligned and closed around the filter to ensure good airflow of clean air. If the filter does not seal well in the housing, dirt and dust can be pulled into the air stream to the cylinders. The shape and size of the air filter element depends on its housing; the filter must be the correct size for the housing or dirt will be drawn into the engine. Battery The battery is the main source of electrical energy for the vehicle. It’s very important that it’s inspected and checked on a regular basis. SHOP TIPS It should be noted that disconnecting the battery on late-model cars removes some memory from the engine's computer and the car's accessories. Besides losing the correct time on its clock or the programmed stations on the radio, the car might run roughly. If this occurs, allow the engine to run for a while before shutting it off. If the battery or any of the associated parts are dirty or corroded, they should be removed and cleaned. Photo Sequence 5 shows the correct procedure for cleaning a battery, a battery tray, and battery cables. SHOP TIPS When removing or installing a battery, always use the built-in battery strap or a battery lifting tool to lift the battery in or out of its tray. PROCEDURE 1. Visually inspect the battery cover and case for dirt and grease. 2. Check the electrolyte level (if possible). 3. Inspect the battery for cracks, loose terminal posts, and other signs of damage. 4. Check for missing cell plug covers and caps. 5. Inspect all cables for broken or corroded wires, frayed insulation, or loose or damaged connectors. 6. Check the battery terminals, cable connectors, metal parts, holddowns, and trays for corrosion damage or buildup-a bad connection can cause reduced cur rent flow. 7. Check the heat shield for proper installation on vehicles so equipped. +++ Automatic transmission fluid (ATF). ------ Typical Procedure for Cleaning a Battery Case, Tray, and Cables P5-1 Loosen the battery negative terminal clamp. P5-2 Use a terminal clamp puller to remove the negative cable. P5-3 Loosen the battery positive terminal clamp. P5-4 Use a terminal clamp puller to remove the positive clamp. P5-5 Remove the battery hold down hardware and any heat shields. P5-6 Remove the battery from the tray. P5-7 Mix a solution of baking soda and water. P5-8 Brush the baking soda solution over the battery case, but don’t allow the solution to enter the cells of the battery. P5-9 Flush the baking soda off with water. P5-10 Use a scraper and wire brush to remove corrosion from the hold-down hardware. P5-11 Brush the baking soda solution over the hold-down hardware and then flush with water. P5-12 Allow the hardware to dry, then paint it with corrosion-proof paint. P5-13 Use a terminal cleaner brush to clean the battery cables. P5-14 Use a terminal cleaner brush to clean the battery posts. P5-15 Install the battery back into the tray. Also install the hold-down hardware. P5-16 Install the positive battery cable. Then install the negative cable. ---------- Transmission Fluid: The oil used in automatic transmissions is called automatic transmission fluid (ATF). This special fluid is dyed red so that it’s not easily confused with engine oil. Before checking the fluid, make sure the engine is warm and the vehicle is level. Then set the parking brake and allow the engine to idle. Sometimes the manufacturer recommends that the ATF level be checked when the transmission is placed into Park; however, some may require some other gear. Make sure you follow those requirements. Locate the fluid dipstick (normally located to the rear of the engine) and pull it out of its tube. Check the level of the fluid on the dipstick. If the level is low, add only enough to bring the level to full. Make sure you only use the fluid recommended by the manufacturer. The condition of the fluid should be checked while checking the fluid level. The normal color of ATF is pink or red. If the fluid has a dark brownish or blackish color and/or a burned odor, the fluid has been overheated. A milky color indicates that engine cool ant has been leaking into the transmission's cooler in the radiator. After checking the ATF level and color, wipe the dipstick on absorbent white paper and look at the stain left by the fluid. Dark particles are normally band and/or clutch material, whereas silvery metal particles are normally caused by the wearing of the trans mission's metal parts. If the dipstick cannot be wiped clean, it’s probably covered with varnish, which results from fluid oxidation. Varnish will cause the transmission's valves to stick, causing improper shifting speeds. Varnish or other heavy deposits indicate the need to change the transmission's fluid and filter. The exact fluid that should be used in an automatic transmission depends on the transmission design and the year the transmission was built. It’s very important that the correct type of ATF be used. Always refer to the service or owner's manual for the correct type of fluid to use. Some transmission dipsticks are also marked with the type of ATF required. Although there are many types of ATF available, the following are the most common: ¦ ATF _3 (Chrysler Specification MS-7176E)-This is a fluid formulated for Chrysler automatic transmissions where ATF+, ATF+2, or ATF +3 is recommended. ¦ Type F-This fluid is typically recommended for Ford and some imported vehicle automatic transmissions built prior to the 1977 model year as well as some 1977 through 1982 models. Don’t assume that all Ford vehicles use type F; they don’t and it has been a long time since they did! ¦ Dexron VI/Mercon-This fluid is sometimes referred to as multipurpose ATF because it’s recommended for all GM and Ford automatic transmissions (since 1983) requiring Dexron or Mercon transmission fluids. It also is suitable for most Mercedes-Benz passenger car automatic transmissions. ¦ Multivehicle ATF-This ATF is specially formulated to meet the requirements of a broad range of automatic transmission specifications. It can be safely used in most U.S. vehicles but should not be used in a few pre-1986 vehicles where type F fluids are specified, in vehicles requiring Dexron VI, or in some recent vehicles equipped with continuous variable transmissions (CVTs). Some transmissions require the use of fluids not mentioned here. CVTs require a fluid that is much different from that used in automatic transmissions. Always use the fluid recommended by the manufacturer. The use of the wrong fluid may cause the trans mission to operate improperly and/or damage the transmission. Manual Transmissions Manual transmissions, transaxles, and drive axle units require the use of specific lubricants or oils, and the levels need to be checked according to the manufacturer's recommended service intervals. Some manufacturers recommend that the fluids be changed periodically. Most repair shops have an air-operated dispenser for these fluids; others rely on a hand-operated oil pump. +++26 A really dirty battery. If hot, add If hot, OK. If cold, add. If cold, OK +++28 Automatic transmission fluid should be checked regularly. Normally the level is checked when the engine is warm. The normal cold level is well below the normal hot level. +++29 A hand-operated pump used to fill transmissions and drive axles with lubricant. +++31 Translucent brake fluid reservoirs allow the fluid level to be observed from the outside. +++30 The filler cap on a power-steering pump normally has a dipstick to check the fluid level. Power-Steering Fluid: Now locate the power-steering pump. The level of power-steering fluid is checked with the engine off. The filler cap on the power-steering pump normally has a dipstick. Unscrew the cap and check the level. The level of the fluid is normally checked when the engine is warm. If the fluid is cold, it will read lower than normal. Add fluid as necessary. Sometimes the fluid used in these systems is ATF; check the service manual for the proper fluid type before adding fluid. Newer master cylinders have a metal or plastic reservoir mounted above the cylinder. The reservoir will have one or two caps. To check the fluid level in the metal reservoir, the cap must be removed. Most often the caps are screwed on. The caps on some plastic reservoirs have snaps to hold them. Unsnap the cap to check the fluid. It’s important to clean the area around the caps before removing them. This prevents dirt from falling into the reservoir. A rubber diaphragm attached to the inside of the caps is designed to stop dirt, moisture, and air from entering into the reservoir. Make sure the diaphragm is not damaged. Most new plastic reservoirs are translucent and allow the fluid level to be observed from the outside. While checking the fluid level, look at the color of the fluid. Brake fluid tends to absorb moisture and its color gives clues as to the moisture content of the fluid. Dark- or brown-colored fluid indicates contamination; the system must be flushed and the fluid replaced. When it’s necessary to add brake fluid, make sure the fluid is the correct type and is fresh and clean. There are basically four types of brake fluids: DOT 3, DOT 4, DOT 5, and DOT 5.1. The specifications for all automotive brake fluids are defined by Society of Automotive Engineers (SAE) Standard J1703 and Federal Motor Vehicle Safety Standard (FMVSS) 116. Fluids classified according to FMVSS 116 are assigned Department of Transportation (DOT) numbers. Basically, the higher the DOT number, the more rigorous the specifications for the fluid. Domestic automakers specify DOT 3 fluid for their vehicles. However, Ford calls for a heavy-duty variation, which meets the basic specifications for Brake Fluid Brake fluid levels are checked at the master cylinder. Older master cylinders are made of cast iron or aluminum and have a metal bail that snaps over the master cylinder cover to hold it in place. Normally the bail can be moved in only one direction. Once moved out of the way, the master cylinder cover can be removed. Once removed, the fluid levels can be checked. Newer master cylinders have a metal or plastic reservoir mounted above the cylinder. The reservoir will have one or two caps. To check the fluid level in the metal reservoir, the cap must be removed. Most often the caps are screwed on. The caps on some plastic reservoirs have snaps to hold them. Unsnap the cap to check the fluid. It’s important to clean the area around the caps before removing them. This prevents dirt from falling into the reservoir. A rubber diaphragm attached to the inside of the caps is designed to stop dirt, moisture, and air from entering into the reservoir. Make sure the diaphragm is not damaged. Most new plastic reservoirs are translucent and allow the fluid level to be observed from the outside. While checking the fluid level, look at the color of the fluid. Brake fluid tends to absorb moisture and its color gives clues as to the moisture content of the fluid. Dark- or brown-colored fluid indicates contamination; the system must be flushed and the fluid replaced. When it’s necessary to add brake fluid, make sure the fluid is the correct type and is fresh and clean. There are basically four types of brake fluids: DOT 3, DOT 4, DOT 5, and DOT 5.1 ( +++32). The specifications for all automotive brake fluids are defined by Society of Automotive Engineers (SAE) Standard J1703 and Federal Motor Vehicle Safety Standard (FMVSS) 116. Fluids classified according to FMVSS 116 are assigned Department of Transportation (DOT) numbers. Basically, the higher the DOT number, the more rigorous the specifications for the fluid. Domestic automakers specify DOT 3 fluid for their vehicles. However, Ford calls for a heavy-duty variation, which meets the basic specifications for DOT 3 but has the higher boiling point of DOT 4. Import manufacturers are about equally divided between DOT 3 and DOT 4. DOT 3, DOT 4, and DOT 5.1 fluids are polyalkylene glycol-ether mixtures, called "polyglycol" for short. The color of both DOT 3 and DOT 4 fluid ranges from clear to light amber. DOT 5 fluids are all silicone based because only silicone fluid-so far-can meet the DOT 5 specifications. No vehicle manufacturer, however, recommends DOT 5 fluid for use in its brake systems. Although all three fluid grades are compatible they don’t combine well if mixed together in a system. Therefore, the best rules are to use the fluid type recommended by the manufacturer and to never mix fluid types in a system. Clutch Fluid--On some vehicles with a manual trans mission, there is another but smaller master cylinder close to the brake master cylinder. This is the clutch master cylinder. Its fluid level needs to be checked, which is done in the same way as brake fluid. In most cases, the clutch master cylinder uses the same type of fluid as the brake master cylinder. However, check this out before adding any fluid. +++ The three types of brake fluid: DOT 3 is the most commonly used. +++Windshield wiper blades are replaced as a complete assembly, or blade inserts are fitted into the blade. Replacement assembly Replacement insert Push button Push-button refill End clip refill End clip Notched flexor refill coin removal +++ Examples of the different ways that wiper blade inserts are secured to the blade assembly. Federal-Mogul Corporation Windshield Wipers Check the condition of the windshield wipers. Wiper blades can become dull, torn, or brittle. If they are, they should be replaced. Also, check the condition of the wiper arms. Look for signs of distortion or dam age. Also, check the spring on the arm. This spring is designed to keep the wiper blade fairly tight against the windshield. If the spring is weak or damaged, the blade won’t do a respectable job cleaning the glass. Most wiper blade assemblies have replaceable blades or inserts. To replace the blades, grab hold of the assembly and pivot it away from the windshield. Once the arm is moved to its maximum position, it should stay there until it’s pivoted back to the windshield. Doing this will allow you to easily replace the wiper blades without damaging the vehicle's paint or glass. There are three basic types of wiper blade inserts. Look carefully at the old blade to deter mine which one to install. Remove the old insert and install the new one. After installation, pull on the insert to make sure it’s properly secured. If the insert comes loose while the wipers are moving across the windshield, the wiper arm could scratch the glass. Most often wiper blades are replaced as an assembly. There are several methods used to secure the blades to the wiper arm. Most replacement blades come with the necessary adapters to secure the blade to the arm. When it’s necessary to replace the wiper arm or the entire assembly, they must be removed. Wiper arms are either mounted onto a threaded shaft and held in place by a nut, or they are pressed over a splined shaft. Some shaft-mounted arms are held in place by a clip that must be released before the arm can be pulled off. When installing wiper arms, make sure they are positioned so the blades don’t hit the frame of the windshield while they are operating. When checking the placement and operation of the wipers, wet the windshield before turning on the wipers. The water will serve as a lubricant for the wipers. Windshield Washer Fluid The last fluid level to check is the windshield washer fluid. Visually check the level and add as necessary. Always use windshield washer fluid and never add water to the washer fluid reservoir, especially in cold weather. The water can freeze and crack the tank or clog the washer hoses and nozzles. Tires: The vehicle's tires should be checked for damage and wear. Tires should have at least 1/16_ of tread remaining. Any less and the tire should be replaced. Tires have "tread wear indicators" molded into them. When the wear bar shows across the width of the tread, the tire is worn beyond its limits. Most shops use a tire wear gauge, which gives an accurate measurement of the tread depth. Also, check the tires for bulges, nails, tears, and other damage. All of these indicate the tire should be replaced. Inflation Check the inflation of the tires. To do this, use a tire pressure gauge. Press the gauge firmly onto the tire's valve stem. The air pres sure in the tire will push the scale out of the tool. The highest number shown on the scale is the air pressure of the tire. Compare this reading with the specifications for the tire. +++Examples of the different ways windshield wiper blades are secured to the wiper arm. Release tab, Bayonet type, Center hinge types, Side latch types, Inner lock type, Pin type, Hook type, Screw type +++ Check the level of the windshield washer fluid at the reservoir. +++ A tire tread depth gauge. The correct tire pressure is listed in the vehicle's owner's manual or on a decal (placard) stuck on the driver's doorjamb. The air pressure rating on the tire is not the amount of pressure the tire should have. Rather this rating is the maximum pres sure the tire should ever have when it’s cold. New vehicles are fit with tire inflation monitoring systems. These systems have an air pressure sensor attached to the inside of each wheel. When the pres sure is below or above a specified range, the vehicle's computer causes a warning light on the dash to illuminate. This alerts the driver of a problem. These monitors can be, and should be, checked, because tire pressure is important to the safety of the vehicle's occupants, and false monitor readings can cause many hardships. Tire Rotation--To equalize tire wear, most car and tire manufacturers recommend that the tires be rotated. Front and rear tires perform different jobs and can wear differently, depending on driving habits and the type of vehicle. In an RWD vehicle, for instance, the front tires usually wear along the outer edges, primarily because of the scuffing and slippage encountered in cornering. The rear tires wear in the center because of acceleration thrusts. To equalize wear, it’s recommended that tires be rotated as illustrated in +++40. Bias ply and bias-belted tires should be rotated about every 6,000 miles. Radial tires should be initially rotated at 7,500 miles and then at least every 15,000 miles thereafter. It’s important that directional tires are kept rotating in the direction they are designed for. This means the tires may need to be dismounted from the wheel, flipped, and reinstalled on the rim before being put on the other side of the car. Lug Nut Torque--Obviously, to rotate the tires you must remove the tire/wheel assemblies and then reinstall them. Before reinstalling a tire/wheel assembly on a vehicle, make sure the wheel studs are clean and not damaged, then clean the axle/rotor flange and wheel bore with a wire brush or steel wool. Coat the axle pilot flange with disc brake caliper slide grease or an equivalent. Place the wheel on the hub. Install the lug nuts, and tighten them alternately to draw the wheel evenly against the hub. They should be tightened to a specified torque and sequence to avoid distortion. Many tire technicians snug up the lug nuts, then when the car is lowered to the floor, they use a torque wrench for the final tightening. Some technicians use a torque absorbing adapter, also called a torque stick, to tighten the lug nuts. Make sure you use the correct stick for the recommended torque. Then check the actual torque of the lug nuts with a torque wrench. !WARNING! Overtorquing of the lug nuts is the most common cause of disc brake rotor distortion. Also, an overtorqued lug distorts the threads of the lug and could lead to premature failure. +++Wheel lugs should be tightened to the specified torque. +++Torque sticks are color coded to indicate their torque setting. +++Check the tires and wheels for damage and proper inflation. +++ A grease gun forces lubrication into a joint through a zerk fitting. -- TIRE PLACARD: Front, rear, and spare tire pressures TPBS TIRE SIZE SPEED RTG RIM COLD TIRE PRESSURE FRT P235/70R15 S 15X7J 220KPA(32PSI) RR P235/70R15 S 15X7J 220KPA(32PSI) SPA P235/70R15 S 15X7J 240KPA(35PSI) MODEL: T10516 PAYLOAD = 348KG(768LB) THIS VEHICLE CONFORMS TO ALL APPLICABLE U.S. FEDERAL MOTOR VEHICLE SAFETY AND THEFT PREVENTION STANDARDS IN EFECT ON THE DATE OF MANUFACTURE SHOWN ABOVE. GVWR GAWR FAT GAWA RA 2200XG(4850LB) 1134KO(2500LB) 1225KG(2700LB) MFD BY B3/99 1GNCT18W4XK187526 TYPE: M.P.V. SEE OWNER'S MANUAL FOR MORE INFORMATION. -- +++39 The tire placard gives the recommended cold tire pressure for that vehicle. LF RF; LR RR; LF RF; LR RR; Radial tires; 5-wheel rotation 4-wheel rotation +++40 Rotation sequence for radial tires. Chassis Lubrication: A PM procedure that is becoming less common because of changing technology is chassis lubrication. However, all technicians should know how to do this. During the lubrication procedure, grease is forced between two surfaces that move or rub against each other. The grease reduces the friction produced by the movement of the parts. During a chassis lube, grease is forced into a pivot point or joint through a grease fitting. Grease fittings are found on steering and suspension parts, which need lubrication to prevent wear and noise caused by their action during vehicle operation. Grease fittings are called zerk fittings and are threaded into the part that should be lubricated. A fitting at the end of a manual or pneumatic grease gun fits over the zerk to inject the lubricant. Older vehicles have zerk fittings in many locations, whereas newer vehicles use permanently lubricated joints. Some of these joints have threaded plugs that can be removed to lubricate the joint. A special adapter is threaded onto the grease gun and into the plug's bore to lubricate the joint. After grease has been injected into the joint, the plug should be reinstalled or a zerk fitting installed. On some vehicles, rubber or plastic plugs are installed at the factory; they should never be reused. Before lubricating the chassis, refer to the ser vice manual and identify the lubrication points for the vehicle. Then raise the vehicle. Locate the lubrication points and wipe the fittings clean with a shop towel. Zerk fittings have a one-way spring-loaded check valve that allows grease into the joint but pre vents it from leaking out. Dirt can plug the valve, allowing grease to leak out and water and dirt to leak in. Carefully look at the joints to see if the joint boots are sealed or not. Some joints, such as tie-rod ends and ball joints, are sealed with rubber boots. If the boots are good, push the grease gun's nozzle straight onto a zerk fitting and pump grease slowly into the joint. If the joint has a sealed boot, put just enough grease into the joint to cause the boot to slightly expand. If the boot is not sealed, put in enough grease to push the old grease out. Then wipe off the old grease and any excess grease. Repeat this at all lubrication points. Greases--Greases are made from oil blended with thickening agents. There are a few synthetic greases available that meet the same standards as petroleum greases. The thickening agent increases the viscosity of the grease. Greases are categorized by a National Lubricating Grease Institute (NLGI) number and by the thickeners and additives that are in the grease, such as lithium, molybdenum disulfide, calcium, aluminum, barium, or sodium. Some greases are also labeled with an "EP," which means they have extreme pressure additives. The number assigned by the NLGI is based on test results and the specifications set by the American Society for Testing Materials (ASTM). The ASTM specifies the consistency of grease using a penetration test. During this test, the grease is heated to 77°F (25°C) and placed below the tip of the test cone. The cone is dropped into the grease. The distance the cone is able to penetrate the grease is measured. The cone will penetrate deeper into soft grease. The NLGI number represents the amount of penetration. The higher the NLGI number, the thicker the grease is. NLGI #2 is typically specified for wheel bearings and chassis lubrication. The NLGI also specifies grease by its use and has established two categories for automotive use. Chas sis lubricants are identified with the prefix "L," and wheel bearing lubricants have a prefix of "G." Greases are further defined within those groups by their over all performance. Chassis greases are classified as either LA or LB, and there are three classifications for wheel bearing greases (GA, GB, and GC). LB and GC have the highest performance ratings and are the greases specified for chassis and wheel bearing lubrication. Many types of greases are labeled as both GC and LB and are acceptable for both. These are often referred to as multipurpose greases. The NLGI certification mark is included on the grease's container. --- Worked Penetration NLGI after 60 strokes Grade at 77°F(25°C) Appearance 000 44.5-47.5 mm fluid 00 4.00-4.30 mm fluid 0 3.55-3.85 mm very soft 1 3.10-3.40 mm soft 2 2.65-2.95 mm moderately soft 3 2.20-2.50 mm semi-fluid 4 1.75-2.05 mm semi-hard 5 1.30-1.60 mm hard 6 0.85-1.15 mm very hard +++44 The table shows the NLGI grades and the worked penetration ranges. --- Class Purpose GA Mild duty-wheel bearings GB Mild to moderate duty-wheel bearings GC Mild to severe duty-wheel bearings LA Mild duty-chassis parts and universal joints LB Mild to severe duty-chassis parts and universal joints +++45 ASTM grease designation guide. -- NATIONAL LUBRICATING GREASE INSTITUTE AUTOMOTIVE WHEEL BEARING LUBRICANT GC NLGI NATIONAL LUBRICATING GREASE INSTITUTE AUTOMOTIVE WHEEL BEARING & CHASSIS LUBRICANT GC-LB NLGI NATIONAL LUBRICATING GREASE INSTITUTE AUTOMOTIVE CHASSIS LUBRICANT LB NLGI +++NLGI identification symbols. 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