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Making the Grade: Annual ASE P2 Test Prep

In this month’s issue, we mostly only address the technical aspects of the test. But there are other questions that deal with other areas such as sales, communication and inventory management. To help you, read on about certain areas you should know.

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p> A little more then three decades ago, the independent, non-profit National Institute for Automotive Service Excellence (ASE) was established. It’s mission was and is simple: To improve the quality of automotive service and repair through the voluntary testing and certification of technicians, parts specialists, machinists and other professions related to the motor vehicle service industry.

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There are currently some 420,000 ASE certified professionals working in the industry.

ASE provides no training, just the testing to prove that you know your stuff.

ASE (through a third party) administers this testing twice a year, in the Spring and in the Fall. The test dates for the Fall testing are November 13, 18 and 20 at some 700 locations around the country. Although the deadline for the Fall test has passed, information on registration and future testing can be found at www.asecert.org.

 

How Certification Works
There are several different parts specialist tests you can take, depending on the kind of skills you have. These tests are not as easy to pass as you might think. In fact, approximately one out of three test takers fails.

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The four tests include:

  • Medium/Heavy Truck Dealership Parts Specialist (P1) – this test reflects the wide range of component systems that a dealership parts specialist must know, as well as communication, sales and inventory management skills.
  • Automobile Parts Specialist (P2) – this test addresses the wide range of skills and knowledge required to work competently in a retail or jobber parts store environment. This month’s ASE Parts Specialists Test prep deals exclusively with this test.
  • Medium/Heavy Truck Aftermarket Parts Specialist (P3) – this is the newest parts specialist test ASE offers. This test reflects the specialization that exists in this segment of the aftermarket. This test was designed so that a candidate could be tested on communication, sales and inventory management. Then test takers must answer questions on the specific vehicle system of their choosing. Two vehicle systems, Brakes and Suspension/Steering, are now available to test takers. Other systems will be added in the future.
  • General Motors Parts Consultant (P4) – this test was developed with GMSPO to assess a candidate’s knowledge required to work competently in a General Motors Dealership parts department.

After passing at least one exam, and after providing proof of two years of relevant work experience, the test taker becomes ASE certified. This certification is valid for five years, and then retesting is required.

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In this month’s issue, we mostly only address the technical aspects of the test. But there are other questions that deal with other areas such as sales, communication and inventory management. To help you, here are the areas you should know:

Store Operations
There are 10 questions in this area. Make sure you are able to perform the following tasks.

  • Calculate discounts, profits, percentages and pro-rated warranties.
  • Calculate special handling charges.
  • Identify and convert units of measure.
  • Determine alphanumeric sequences.
  • Determine sizes with precision measuring tools and equipment.
  • Perform money transactions (cash, checks, credit and debit cards).
  • Perform sales and credit invoicing.
  • Interact with management and fellow employees.
  • Understand the value of housekeeping skills (facility, work stations, and backroom).
  • Assist with training.
  • Identify potential safety risks; Demonstrate proper safety practices.
  • Identify proper handling of regulated and/or hazardous materials.
  • Identify potential security risks.
  • Identify industry terminology.
  • Understand the value of company policies and procedures.
  • Understanding the basic functions of tools and equipment used in automotive service.

 

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Customer Relations & Sales
There are 11 questions in this area. Be sure you are able to:

  • Identify customer types and skill level.
  • Identify customer needs.
  • Provide information to customers.
  • Handle customer complaints and returns.
  • Acknowledge and greet customers.
  • Demonstrate proper telephone skills.
  • Obtain pertinent application information.
  • Present a knowledgeable and professional image.
  • Recognize the value of selling related items.
  • Identify product features and benefits.
  • Handle customer objections.
  • Balance telephone and in-store customers.
  • Promote store services and features.
  • Promote upgraded products.
  • Solve customer problems.
  • Close the sale.

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Vehicle Identification
There are three questions in this area:

  • Locate and utilize VIN.
  • Locate production dates.
  • Locate and utilize component ID data.
  • ID body styles.
  • Use additional reference sources for interpreting component information.
  • Locate paint codes.

Cataloging Skills
There are seven questions that will test your knowledge of cataloging skills:

  • Locating the proper catalog and ID the right parts.
  • Obtain and interpret additional information such as footnotes and illustrations.
  • Use additional sources like interchange lists, tech bulletins and supplements.
  • ID catalog terminology and abbreviations.
  • Perform catalog maintenance.

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Inventory Management
There will be two questions on inventory management, including:

  • Lost sales reports.
  • Verification of outgoing and incoming merchandise.
  • Physical inventories.
  • Stock rotations.
  • Special orders.
  • Core handling.
  • Proper handling of returns and warranties.
  • Determining the proper selling units (each, pair, case, etc.)
  • Handle the return of broken kits, special ordered parts and exchanges.
  • Account for store use items.

Merchandising
There will be two questions on merchandising:

  • Display strategy.
  • Display pricing.
  • How to inspect and maintain shelf quantities and condition.
  • Impulse and seasonal items.
  • Sales aids.

 

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Technical Areas
What follows are 13 articles that are based on technical areas of the ASE P2 Task List. Keep your pencils sharpened, keep your eyes on your own paper and good luck!


ASE AUTOMATIC TRANSMISSION

Editor’s Note: There will be two questions on the P2 test that deal specifically with automatic transmissions.

An automatic transmission shifts itself using engine rpm, load and other inputs to regulate shift points and gear engagement. Older automatics have mechanical/hydraulic controls, while newer automatics have electronic/ hydraulic controls and are operated by a computer (the powertrain control module or a separate transmission control module). All automatics require some type of oil for the hydraulics as well as lubrication. Due to the complexity of the transmission, internal failures typically require replacing the entire transmission or transaxle with a new or remanufactured unit. Except for gaskets and filters, most internal transmission parts are dealer only parts.

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VALVE BODY AND OTHER CONTROLS
The valve body is located inside the transmission oil pan and regulates gear shifts and clutch pack engagement. Other shift controls on some transmissions include a vacuum modulator and/or governor (used on older transmissions to modify the rpm at which the transmission upshifts when the vehicle is accelerating under load). The modulator is mounted on the side of the transmission and is connected by a vacuum hose to the intake manifold on the engine. Problems with either component will affect shifting. Older transmissions may also use a throttle cable or linkage for kickdown shifts when accelerating. Newer transmissions use shaft and vehicle speed sensor inputs and engine sensor inputs to regulate shifting.

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ATF
Automatic Transmission Fluid (ATF) is the working fluid inside an automatic transmission. It lubricates the gears, bearings and bushings, carries hydraulic pressure to shift the gears and serves as a fluid coupling inside the torque converter to transfer engine torque to the transmission. The fluid level inside the transmission must be maintained between the FULL and ADD marks for proper transmission operation. The fluid should also be changed if it shows signs of oxidation (dark discoloration or burned odor) or at the interval recommended in the owners manual.

ATF is a lightweight mineral oil that contains special additives and friction modifiers. It is dyed red to distinguish it from motor oil. Different types of ATF are required for different makes and models of transmissions, so make sure your customer gets the correct type of fluid for his vehicle. Using the wrong ATF can cause shift problems and may damage the transmission.

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GM, Ford, Chrysler, Honda, Mercedes and others all have their own specifications for ATF. There’s no such thing as a "universal" ATF that works in all transmissions. Some fluids meet a variety of specifications but cannot meet them all because of the different friction additives that are required.

Ford has three automatic transmission fluid specifications: Type F (a non-friction modified formula for most 1964-81 transmissions), Mercon (a friction-modified ATF similar to Dexron II for 1988-97 transmissions) and Mercon V (Ford’s latest friction-modified formula, introduced in 1997).

General Motors has two specifications: Dexron II and III. Both are friction-modified formulas and Dexron III can be used in the older GM transmissions that originally required Dexron II.

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Chrysler has a number of different ATFs: MS-7176D (also known as ATF+2) is Chrysler’s version of a friction-modified ATF that’s similar to Dexron II. But Chrysler’s fluid is more slippery than GM’s, so Chrysler recommends using only ATF that meets their specifications in Chrysler transmissions. In other words, do not use Dexron or Mercon in a Chrysler transmission.

Chrysler MS-7176E (also known as ATF+3) was introduced in 1998 and supersedes ATF+2. It should only be used in 1998 and newer Chrysler transmissions, but it can also be used in earlier Chrysler transmissions. Chrysler ATF+4 is for 2000-01 model-year applications, and their newest fluid ATF+5 is for 2002 and newer models.

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ATF FILTER
Located inside the transmission pan, the ATF filter traps wear particles that could damage the transmission. The filter should be replaced when the fluid is changed. A new transmission pan gasket is also required.

 

ATF OIL COOLER
Original equipment ATF coolers are usually located in the bottom or the side of the radiator and are connected to the transmission with a pair of lines. Fluid circulates from the transmission to the cooler to maintain and limit the temperature of the ATF. For towing or hard use, installing an aftermarket auxiliary ATF cooler can help keep ATF temperatures down to prolong the life of the fluid and transmission.

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TORQUE CONVERTER
The torque converter is a fluid coupling mounted on the flywheel between the engine and transmission that transfers engine torque to the transmission and also provides "torque multiplication" much like a set of reduction gears. Inside is a three-piece set of closely spaced blades, the turbine, stator and impeller. As the torque converter rotates, fluid is thrown from one set of blades against the other, much like a propeller churning water. This pushes the blades connected to the transmission input shaft and planetary gears to drive the vehicle down the road. Torque converters in most newer vehicles have a "lockup clutch" that engages in 3rd and 4th gears to eliminate slippage for improved fuel economy. The lockup clutch is engaged hydraulically and controlled by an electronic solenoid valve. The torque converter holds approximately one third of the total fluid required by the transmission. A failure results in slugging acceleration.

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TRANSAXLE
The transaxle is a transmission in a front-wheel drive car or minivan. A transaxle combines the transmission and differential into one unit.


ASE BRAKES


Editor’s Note: There will be three questions on the P2 test that deal specifically with brakes.

The brake system includes the master cylinder, power booster, disc brake calipers and rotors, wheel cylinders and brake drums, brake hardware, brake hoses and lines, various valves, disc brake pads and drum shoes and brake fluid. On vehicles equipped with antilock brakes (ABS), additional parts include up to four wheel speed sensors, the ABS hydraulic modulator and control module, and a pump motor and accumulator (not used on some systems).

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When the driver steps on the brake pedal, it moves a rod in the master cylinder forward to push a pair of pistons against fluid in the primary and secondary chambers. Brake systems are split into two separate hydraulic circuits. Each circuit operates two of the four brakes (both fronts, both rears or a diagonal pair). This is a safety requirement so if one circuit fails, at least two brakes will continue to operate so the vehicle can be stopped.

Brake fluid carries the hydraulic pressure created in the master cylinder through the brake lines to the front calipers and rear calipers or drums to apply the brakes. Most older vehicles have front disc brakes and drums in the rear, but many newer cars, SUVs and trucks have disc brakes front and rear. When pressure reaches the brakes, the pads are squeezed against the rotors, and if the vehicle has drums in the rear, the shoes are pushed out against the drums to generate friction and stop the vehicle.

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On vehicles equipped with power brakes, a brake booster located behind the master cylinder on the firewall multiplies the force of the brake pedal input using engine vacuum and a large diaphragm. This reduces the pedal effort needed to stop the vehicle. On some older vehicles with integral ABS systems, the ABS pump and accumulator provide power assist.

Additional parts involved in the braking process include a pressure differential valve (a safety switch that turns on the brake warning lamp if there’s a loss of pressure in either brake circuit), a proportioning valve to reduce pressure to the rear brakes for more balanced braking (not used on all vehicles) and on some a load-sensing proportioning valve to increase or decrease hydraulic pressure to the rear brakes based on vehicle loading.

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MAJOR COMPONENTS
The major wear components in the brake system are the disc brake pads and drum shoes. Every time the brakes are applied, these parts are subjected to friction and wear.

Lining life depends on how the vehicle is driven. Stop-and-go city driving, mountain driving and aggressive driving all involve more frequent braking, harder braking and higher brake temperatures – all of which adds up to more wear and shorter lining life. Highway driving and gradual, light braking produce less lining wear and longer lining life.

On most vehicles, the front linings wear out twice as fast as the rear linings, so when the linings need to be replaced for the first time, it’s usually only the front pads that need to be changed. Replacement linings should be the same or better than the original linings. Semi-metallic linings are often used in high-heat applications because they can withstand high operating temperatures without fading or wearing excessively. Other high-temperature friction materials include linings with ceramic content. Pads and shoes with nonasbestos organic (NAO) linings are typically used for lower-heat applications such as rear brakes and front brakes on rear-wheel drive cars and trucks.

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ROTORS & DRUMS
When linings are replaced, the rotors and drums may need to be resurfaced or replaced depending on their condition. If a rotor is worn to minimum thickness, or a drum is worn to maximum diameter, replacement is necessary. Most rotors are made of cast iron, but composite rotors have a thin, stamped steel center hat attached to a cast iron rotor ring. Composite rotors are more difficult to resurface and more prone to pedal pulsation problems than one-piece cast rotors. They are also more expensive than cast. Composite rotors can be replaced with cast rotors as long as both rotors are replaced at the same time (don’t intermix different kinds of rotors side to side).

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Most front rotors are vented, while most rear rotors are not because more cooling is usually needed for the harder-working front brakes. Most rotors are interchangeable left to right, but some are directional, so pay close attention to the catalog listings when looking up part numbers. New rotors are ready to install and do not require additional resurfacing (turning rotors unnecessarily shortens their service life).

Other parts that wear out over time include hydraulic components such as the calipers, wheel cylinders and master cylinder.

 

CALIPERS
Most calipers have one or two pistons, but some have up to four pistons mounted in a rigid housing. Most calipers are cast iron (though some are aluminum) with steel or molded phenolic (plastic) pistons. Most calipers are a floating design with slides or bushings that allow the caliper to move sideways and center itself over the rotor when the brakes are applied. Others are a fixed design with rigid mounts and do not move. If the slides or bushings on a floating caliper become badly corroded or worn, it may prevent the caliper from sliding, causing uneven pad wear. The inside pad will wear faster than the outside pad. If a piston in either type of caliper sticks, the caliper may not release, which can cause the brake to drag, rapid pad wear on one side, uneven braking and a pull to one side when the brakes are applied. Leaky piston seals will allow brake fluid to contaminate the brake linings. Leaky calipers must be rebuilt or replaced. Loaded calipers come ready to install with new pads. Bare calipers do not include pads. On vehicles with four-wheel disc brakes, the rear calipers may also include some type of parking brake mechanism. This makes the calipers more complicated and expensive to replace.

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WHEEL CYLINDERS
The wheel cylinders inside drum brakes have two opposing pistons that move outward when pressure is applied. The wheel cylinder is mounted on the brake backing plate, and has dust seals over the pistons to keep out dust and water. Each piston has a cup-shaped seal for the fluid inside. Common problems with wheel cylinders include fluid leaks and sticking. Wheel cylinders can be rebuilt or replaced. Leaking fluid can contaminate the brake shoes, requiring their replacement as well.

Wear in the master cylinder may allow fluid to leak past the piston or shaft seals. A symptom of a bad master cylinder is a brake pedal that slowly sinks to the floor when braking at a stop light. Leaks or failure to hold pressure require rebuilding or replacing the master cylinder. Rebuilding aluminum master cylinders is not recommended. On some older vehicles with ABS, the master cylinder is part of the ABS modulator and is very expensive to replace.

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Rubber brake hoses can also deteriorate with age and leak. Any hose that is cracked, bulging, leaking or damaged should be replaced without delay because of the danger of brake failure should the hose leak. Steel brake lines can corrode internally or externally. Replacement brake lines must be steel with double-flared or ISO end fittings.

 

BRAKE FLUID
Brake fluid also wears out over time and should be replaced when the brakes are serviced.

The main issue here is moisture contamination that causes a breakdown of corrosion inhibitors in the fluid and lowers the fluid’s boiling temperature (which increases the risk of fluid boil and pedal fade under hard use). DOT 3 and DOT 4 brake fluid are the two main types and both are glycol-based hydraulic fluid. DOT 5 fluid is a silicone-based fluid and is used only for special applications (like older vehicles that sit for long periods of time or are operated in extremely wet environments). DOT 4 has a higher temperature rating than DOT 3 and is used in many European vehicles. Use the type of fluid specified by the vehicle manufacturer.

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Related items that may also need to be replaced when servicing the brakes include the wheel bearings and seals. On older vehicles with serviceable wheel bearings, the grease seals should always be replaced when the bearings are cleaned and repacked with grease. Special high-temperature wheel bearing grease is required (never ordinary chassis grease).

Disc and drum brake hardware should also be replaced when the brakes are serviced. Drum hardware includes the return springs, holddown springs, self-adjusters and other cables, clips or springs used in the brake assembly. Return springs that pull the shoes back away from the drum when the brakes are released may become weak with age, allowing the brakes to drag. Self-adjusters can become corroded and stick, causing increased pedal travel as the shoes wear. On disc brakes, the hardware includes slides and bushings that can become worn and corroded and anti-rattle clips and springs that reduce noise. A high-temperature, moly-based brake grease should be used to lubricate slides, bushings and shoe pads on drum brake backing plates.

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ASE COOLING

Editor’s Note: There will be two questions on the P2 test that deal specifically with cooling systems.

The cooling system includes the radiator, radiator cap, coolant reservoir, fan, water pump, thermostat, hoses, belts and antifreeze. Related parts include the coolant sensor and fan relay.

The radiator’s job is to cool off the hot coolant after it leaves the engine block. The radiator is mounted up front so it gets good airflow when the vehicle is moving. But when the vehicle is stopped or traveling at low speed, additional airflow must be provided by a belt-driven or electric fan. The fan also operates when the A/C is on.

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The radiators in most late-model vehicles are aluminum with plastic end tanks. Most older vehicles have copper/brass radiators. Both types are vulnerable to internal corrosion caused by coolant neglect. Leaks can sometimes be stopped by adding a sealer product to the coolant, but eventually the radiator will have to be repaired or replaced if it is leaking. Replacement radiators should have the same cooling capacity (or better) as the original and the same hose connections. Cooling capacity is determined by the thickness of the radiator, the number of fins and tubes and/or the design of the fins and tubes. Increased cooling capacity is recommended for towing and performance applications.

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Connected to the radiator by a tube or hose is a plastic coolant reservoir. The reservoir typically holds up to a quart of coolant and prevents the loss of coolant if the engine overheats. The coolant level is maintained at the reservoir (never open a hot radiator cap!)

The radiator cap seals the radiator and pressurizes the coolant inside. This raises the temperature at which the coolant normally boils for added boilover protection during hot weather. System pressure ratings vary from five to 15 psi. A weak spring in the cap or a leaky seal can allow coolant to escape from the radiator, which may lead to overheating. Pressure testing the radiator cap will reveal its condition. If the cap can’t hold its rated pressure, it must be replaced with one that has the correct pressure rating for the application.

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The water pump is the heart of the cooling system. It circulates coolant between the engine and radiator to keep the engine at normal operating temperature. The pump is belt-driven and consists of an impeller mounted on a shaft inside a cast or stamped steel housing. The pump is usually mounted on the front of the engine. On some overhead cam (OHC) engines, the pump is mounted under the timing belt and requires considerable labor to replace. For this reason, you should recommend replacing the pump if the timing belt is being replaced for scheduled maintenance (recommended every 60,000 to 100,000 miles depending on the application.) The service life of the water pump and timing belt are about the same, so changing both at the same time can save the vehicle owner money on future repairs. Water pumps don’t last forever, and leaks around the pump shaft seal and bearing can quickly lead to overheating. Any water pump that is leaking, making noise or has excessive shaft play should be replaced. Replacement options include remanufactured and new pumps.

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The water pump may also be driven by a V-belt or a flat serpentine belt. The same belt may also drive other engine accessories. Belts deteriorate with age and should be replaced if frayed, cracked, glazed or oil-soaked. Replacement belt length and width must be the same as the original. On vehicles with serpentine belts, the automatic tensioner may also need to be replaced if it’s sticking, making noise or cannot maintain proper belt tension. Belt idler pulleys should also be replaced if noisy, worn or sticking.

For temperature control, the cooling system requires a thermostat. It is usually located in a housing where the upper radiator hose connects to the engine. The thermostat does two things: it allows the engine to warm-up quickly (which reduces cold emissions and fuel consumption) and to maintain a consistent operating temperature (also important for low emissions, good fuel economy and performance). The thermostat has a temperature-sensitive valve that remains closed and blocks the flow of coolant until the engine reaches 195 to 210 degrees. It then opens and allows coolant to flow to the radiator. The thermostat continues to cycle open and shut so the engine will run within a certain temperature range. This is very important on late-model vehicles with computer engine controls because engine temperature affects the fuel feedback control loop, emissions, fuel economy and performance.

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If the thermostat sticks shut, the engine will overheat. If it fails to close, the engine will be slow to warm-up, and the heater may not put out much heat when the weather turns cold. Fuel economy, emissions and engine wear will also suffer. Under no circumstances should an engine be run without a thermostat. Replacement thermostats should have the same rating as the original. A slightly hotter thermostat may be used during cold weather for increased heater output, but a colder thermostat should not be used on engines with computer controls. Other items that may be needed when changing a thermostat include a new thermostat housing and gasket or sealer.

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To improve cooling, a fan is needed to pull air through the radiator when the vehicle is stopped or traveling at low speed. Older, rear-wheel-drive vehicles may have a belt-driven fan with or without a clutch. The clutch allows some slippage and is used to reduce fan noise at high rpm and to improve fuel economy by reducing drag. Excessive slipping in the clutch, however, may reduce airflow and cause the engine to overheat at low speed. Most newer vehicles have one or two electric cooling fans mounted behind the radiator, and a few have hydraulic fans driven by power steering fluid. Electric fans are powered through a relay and controlled by a coolant temperature switch or the engine computer. A failure of the fan motor, fan relay, coolant temperature switch or a wiring problem that prevents the fan from coming on can cause the engine to overheat.

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The major hoses in the cooling system include the upper and lower radiator hoses (the lower one usually attaches to the water pump, and the upper usually attaches to the thermostat housing), plus a pair of heater hoses (one inlet and one outlet) and various connecting hoses and bypass hoses depending on the application. Original equipment hoses are usually molded (preformed) to fit a particular vehicle. Aftermarket replacement hose may be molded (which sometimes requires cutting to length), or straight or ribbed (flexible) to fit a wider variety of applications. Replacement hoses must be the same length and diameter as the original. New clamps should also be installed when hoses are replaced. Hoses should be replaced if leaking, cracked or bulging. Electro chemical degradation (ECD) due to coolant neglect can cause hoses to fail from the inside out.

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The coolant that carries heat from the engine to the radiator is a mixture of ethylene glycol antifreeze and water (typically a 50/50 mix.) This combination provides freezing protection down to -34 degrees F and boilover protection up to 265 degrees F with a 15 psi radiator cap. The condition of the coolant is just as important as the strength because corrosion can attack the system from within if the coolant is neglected. The recommended replacement interval for traditional green antifreeze is two years or 30,000 miles. For the newer long-life coolants, the change interval can be as long as five years or 150,000 miles. Most long-life coolants use organic acid technology (OAT) additives that are different from those used in standard antifreeze. Long-life coolants may contain special dyes to distinguish them from ordinary antifreeze. General Motor’s Dex-Cool is dyed orange, for example. Different types of antifreeze should not be intermixed as doing so may reduce the ability of long-life products from protecting the cooling system from corrosion.

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ASE DRIVETRAIN

Editor’s Note: There will be two questions on the P2 test that deal specifically with drive train components. These components include driveshafts, half shafts, U-joints, CV joints and four-wheel drive systems.

The drivetrain consists of everything between the transmission and wheels. On rear-wheel-drive (RWD) cars and trucks, this includes the driveshaft, universal joints, differential and axles. On front-wheel-drive (FWD) cars and minivans it includes the halfshafts, constant velocity joints (CV) and hub assemblies, and on all-wheel-drive (AWD) cars and SUVs and four-wheel-drive (4WD) trucks, it includes a transfer case.

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The most often replaced drivetrain components on RWD vehicles are the U-joints. On FWD vehicles, it’s the CV joints. Both are components that eventually wear out.

U-joints are mounted on both ends of the driveshaft on RWD vehicles so the driveline can move up and down to follow the motions of the suspension. Each U-joint consists of a four-point center cross with needle bearing cups mounted in a pair of yokes. Vehicles with two-piece driveshafts have additional U-joints and/or a CV joint where the two shafts are joined and supported by a center carrier bearing.

U-joints are "phased" (positioned) 90 degrees to one another to reduce driveline vibrations. Almost all late-model OE U-joints are sealed, but some older vehicles have grease fittings for extended life. Some aftermarket replacement U-joints are also avail

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