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ASE T3 Drive Train (Medium/Heavy Truck) study materials
ASE T3 Drive Train (Medium/Heavy Truck) study resources

ASE T3 Drive Train (Medium/Heavy Truck) practice questions

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Question 1Clutch

What is the primary job of the clutch in a medium-duty truck drivetrain?

  1. To hold engine speed steady regardless of load
  2. To multiply engine torque before it reaches the transmission
  3. To engage and disengage engine torque smoothly Correct answer.
  4. To reverse the direction of rotation between engine and driveshaft

Explanation

The clutch connects and disconnects engine torque to the transmission so the truck can start from rest and shift gears without shock. Torque multiplication happens in the transmission and final drive, not in the clutch. Engine speed is regulated by the governor, and direction reversal is handled by the transmission and axle.

Question 2Clutch

Clutch pedal free play is best described as:

  1. The distance the pedal moves after the clutch begins to disengage
  2. The distance the release fork moves when the clutch is fully disengaged
  3. The total pedal travel from rest to the floor stop
  4. Pedal travel before the release bearing touches the pressure plate Correct answer.

Explanation

Free play is the pedal movement that takes up linkage clearance before the release bearing contacts the pressure plate release fingers. Without it, the bearing rides on the fingers continuously, wears quickly, and can hold the clutch partially released; too much free play can prevent full disengagement.

Question 3Clutch

What is the function of the clutch release (throwout) bearing?

  1. It carries engine torque from the flywheel to the clutch disc
  2. It absorbs torsional vibration between the engine and transmission
  3. It centers the transmission input shaft in the crankshaft hub
  4. It converts pedal force into axial force Correct answer.

Explanation

The release bearing is the rotating link between the stationary release mechanism and the spinning pressure plate. When the pedal is applied, the fork moves the bearing into the release fingers, which unloads clamp force on the disc. Engine torque is carried by the pressure plate and disc, not by the bearing.

Question 4Clutch

A clutch disc is removed for inspection and the facing is worn until the rivet heads are nearly flush with the friction surface. What should be done?

  1. Reinstall the disc because rivets flush with the facing are normal
  2. Install shims under the pressure plate to restore clamp load
  3. Grind the rivet heads flush and reuse the disc
  4. Replace the clutch disc Correct answer.

Explanation

A disc is worn out when the rivet heads are flush with or below the friction surface. Continued use lets the rivets score the flywheel, and the reduced friction surface causes slipping and overheating. A worn disc must be replaced, not machined, shimmed, or reused.

Question 5Clutch

The pilot bearing or bushing in a manual transmission truck is located at which point?

  1. In the crankshaft hub or flywheel center Correct answer.
  2. At the release fork pivot ball
  3. In the center of the pressure plate diaphragm
  4. In the rear extension housing, supporting the output shaft

Explanation

The pilot bearing or bushing sits in the crankshaft hub or flywheel center and supports the forward end of the transmission input shaft. It keeps the input shaft and clutch disc aligned with the crankshaft centerline. The output shaft is supported by bearings in the transmission case and extension housing.

Question 6Clutch

The clutch fluid level in a hydraulically operated clutch master cylinder reservoir is low. What is the most appropriate first step?

  1. Inspect for leaks and add the specified fluid Correct answer.
  2. Top off with engine oil and return the truck to service
  3. Bleed the system and ignore the fluid level
  4. Replace the clutch disc

Explanation

A low reservoir on a hydraulic clutch usually means fluid is escaping past a seal or fitting, so the leak must be located before the level is corrected. Only the fluid the manufacturer specifies should be added, because the wrong fluid can damage seals. A low hydraulic fluid level does not point to the clutch disc.

Question 7Clutch

What is the purpose of the clutch starter interlock switch on a manual transmission truck?

  1. It releases the clutch automatically during cranking
  2. It prevents cranking unless the clutch pedal is depressed Correct answer.
  3. It adjusts clutch free play as the disc wears
  4. It disengages the clutch at governed engine speed

Explanation

The interlock switch completes the starter circuit only when the clutch pedal is depressed. That prevents the truck from lurching forward if the transmission is in gear when the engine is cranked. It has no role in clutch adjustment, clutch release during driving, or engine speed control.

Question 8Clutch

Before a clutch disc is installed on a transmission input shaft, the splines should be:

  1. Coated with wheel bearing grease
  2. Left clean and completely dry
  3. Lightly lubricated with the specified spline lubricant Correct answer.
  4. Coated with anti-seize compound

Explanation

The disc hub must slide freely on the input shaft splines as the clutch engages and releases, so a light coat of the specified high-temperature spline lubricant is applied. Excess grease or the wrong product can be thrown onto the friction facings and cause chatter or slippage. Dry, rusted splines can make the disc stick and cause drag.

Question 9Clutch

Compared with a coil-spring pressure plate, a diaphragm-spring clutch generally:

  1. Relies on centrifugal force to increase clamp load at speed
  2. Cannot be used with an organic-faced clutch disc
  3. Needs more pedal effort but engages more abruptly
  4. Needs less pedal effort and holds clamp load more consistently Correct answer.

Explanation

A diaphragm spring has a flatter clamp-load curve and lower release force than a coil-spring design with release levers. That gives lighter pedal effort and more consistent clamp load as the disc wears. Organic facings work with either design, and centrifugal assist is characteristic of coil-spring release levers.

Question 10Clutch

What is the purpose of the torsional damper springs in a clutch disc hub?

  1. Keep the clutch disc centered on the flywheel surface
  2. Return the release bearing to its rest position
  3. Absorb driveline torsional vibration and reduce rattle Correct answer.
  4. Increase the clamp load as engine speed rises

Explanation

Damper springs allow a few degrees of torsional compliance in the disc hub so engine firing pulses are not fed directly into the driveline. That reduces gear rattle and driveline shock. Broken or worn damper springs cause rattle and noise but do not change clamp load, bearing return, or disc centering.

Question 11Clutch

On a heavy truck with a two-plate clutch, how is the clutch brake applied?

  1. An air cylinder that applies whenever the parking brake is set
  2. Moving the pedal past disengagement until the bearing contacts it Correct answer.
  3. A spring-loaded cone in the synchronizer locks the input shaft
  4. The release bearing presses the disc against the flywheel

Explanation

The clutch brake is a friction disc on the transmission input shaft that is squeezed when the release bearing travels beyond the clutch-release point. It is applied only in the last part of pedal travel, near the floor, to stop the input shaft so a gear can be selected from a standstill. It is not operated by the synchronizers or the air brake system.

Question 12Clutch

A truck clutch slips when pulling a grade under load. Which condition is the most likely cause?

  1. Air trapped in the hydraulic release circuit
  2. Excessive clutch pedal free play
  3. A warped flywheel that still has normal clamp load
  4. Insufficient clamp load or oil-contaminated facings Correct answer.

Explanation

Slipping under load means the clutch cannot transmit engine torque, which points to low clamp load, a worn or glazed disc, oil contamination, or a weak pressure plate. Excessive free play and trapped air cause incomplete release, which shows up as drag and gear clash rather than slip. A warped flywheel mainly causes chatter or pedal pulsation.

Question 13Clutch

A clutch that fails to release completely when the pedal is depressed will typically cause:

  1. A pulsating pedal with otherwise normal shifts
  2. Clutch slippage under heavy acceleration
  3. A howl that appears only when the pedal is depressed
  4. Hard shifting and gear clash, especially from a stop Correct answer.

Explanation

When the clutch does not fully release, the input shaft keeps turning and the synchronizers must overcome engine torque, so gears clash and engagement is hard, especially from a standstill. Slippage and pedal pulsation are different faults. A howl only with the pedal depressed points to the release bearing.

Question 14Clutch

Which of the following is a common cause of clutch chatter during engagement?

  1. Excessive clutch pedal free play
  2. A worn release bearing
  3. A misadjusted clutch brake
  4. Oil on the facings, a warped flywheel, or loose mounts Correct answer.

Explanation

Chatter comes from uneven engagement, most often from oil or grease on the facings, a warped or improperly machined flywheel, worn engine or transmission mounts, or a bent disc. Free play too tight or too loose affects release and bearing life rather than engagement smoothness. Clutch-brake adjustment affects release and stopping of the input shaft, not chatter.

Question 15Clutch

During a clutch replacement, the flywheel shows fine, shallow heat-check cracks and light scoring. What is the recommended service?

  1. Sand the surface with emery cloth and reuse it
  2. Weld the cracks and resurface the friction face
  3. Machine it within specification or replace it Correct answer.
  4. Replace it only when the cracks can catch a fingernail

Explanation

Light surface heat checks can be removed by machining the flywheel within the manufacturer's limits, provided the friction surface and step height finish in specification. Cracks that catch a fingernail or extend into the hub are grounds for replacement because they can grow and crack the flywheel. Sanding or welding is not an approved repair.

Question 16Clutch

After a mechanical clutch linkage adjustment, pedal free play is set almost to zero. What is the likely result?

  1. The clutch brake will not operate at all
  2. The release bearing will ride on the fingers and wear rapidly Correct answer.
  3. Clutch torque capacity will increase slightly
  4. The clutch will not fully disengage and will drag

Explanation

Free play lets the release bearing retract fully so the pressure plate applies its full clamp load. With little or no free play, the bearing is preloaded against the release fingers, spins constantly, wears quickly, and can hold the clutch partially released, causing slip and heat.

Question 17Clutch

A heavy truck has an air-assisted clutch linkage and the pedal has become very hard to depress with no apparent assist. Which is the most likely cause?

  1. Worn input shaft splines
  2. A glazed clutch disc
  3. A faulty assist cylinder, control valve, or low air supply Correct answer.
  4. A leaking rear wheel seal

Explanation

An air-assisted linkage uses air pressure to reduce pedal effort, so a hard pedal with no assist points to the assist cylinder, its control valve, or the air supply and lines feeding it. A glazed disc causes slip, worn splines cause drag or noise, and a wheel seal leak affects the brakes, not pedal effort.

Question 18Clutch

A hydraulic clutch system has been opened for repair. After reassembly, the pedal feels spongy and the clutch drags. What is the correct action?

  1. Replace the clutch disc and pressure plate
  2. Bleed the hydraulic system to remove trapped air Correct answer.
  3. Tighten the pedal free play adjustment
  4. Increase the clutch brake clearance

Explanation

Air in a hydraulic clutch circuit compresses instead of transmitting full pedal travel, so the release bearing does not stroke far enough and the clutch drags. Bleeding at the slave cylinder removes the trapped air and restores a firm pedal. Free-play, disc, and clutch-brake adjustments will not correct a spongy pedal caused by air.

Question 19Clutch

The clutch brake on a heavy truck is correctly adjusted when it:

  1. Stays applied continuously while the truck is moving
  2. Contacts only after the clutch is fully disengaged, near the floor Correct answer.
  3. Contacts as soon as the pedal begins to move
  4. Never contacts the release bearing at any point

Explanation

Correct clutch-brake adjustment gives full clutch release before the brake is applied, with contact only in the last part of pedal travel. If it applies too early, the clutch cannot release cleanly and shifts clash; if it is applied while the truck is moving, the brake burns out.

Question 20Clutch

Some flywheels have a raised friction surface step. Why must the step height be maintained when the flywheel is machined?

  1. It determines the pilot bearing press fit
  2. It has no effect as long as the clutch is new
  3. It sets the ignition timing reference
  4. It sets installed clamp load and release bearing geometry Correct answer.

Explanation

The step height between the friction surface and the mounting surface sets how far the pressure plate sits from the flywheel, which determines installed clamp load and where the release fingers sit. Machining the step away can cause slip or incomplete release even with a new clutch. Ignition timing and pilot bearing fit are unrelated.

Question 21Clutch

How does a pull-type clutch release the disc?

  1. The release fork rotates to multiply pedal effort
  2. The release bearing pushes the diaphragm spring toward the flywheel
  3. The release bearing pulls the release fingers away from the flywheel Correct answer.
  4. Centrifugal force applies the clutch as engine speed rises

Explanation

In a pull-type clutch, the release bearing moves rearward and pulls the release fingers away from the flywheel so clamp load on the disc is removed. A push-type bearing moves forward and pushes the fingers inward instead. The two designs use different bearings, sleeves, and linkage geometry and cannot be interchanged.

Question 22Clutch

A self-adjusting clutch has an adjuster ring that has not moved despite significant disc wear, and the clutch now slips. Which condition best explains this?

  1. The release bearing is set much too far from the release fingers
  2. The adjuster is seized or its wear sensor is damaged Correct answer.
  3. The clutch brake has been adjusted too tight
  4. The flywheel friction surface is thinner than specified

Explanation

A self-adjusting clutch uses an adjuster ring and one-way mechanism to compensate for disc wear so the diaphragm stays at its designed angle and keeps clamp load. If the ring seizes or the wear sensor is damaged, compensation stops and clamp load falls as the disc wears, causing slip. Brake adjustment, bearing position, and flywheel thickness are separate concerns.

Question 23Clutch

A newly installed clutch chatters and the pedal pulsates. Flywheel runout checks were within specification, but heavy paint and debris were found on the transmission-to-engine mounting surface. What is the best explanation?

  1. The release bearing is defective
  2. The clutch disc was installed backward
  3. The pilot bearing is too tight in the crankshaft
  4. Debris under the bell housing tilted the transmission, causing runout Correct answer.

Explanation

The transmission must sit flat and square on the engine block so the input shaft is coaxial with the crankshaft. Paint, debris, or a bent block plate tilts the bell housing and produces clutch runout, chatter, and pedal pulsation even with a new clutch. The runout checks would look acceptable if the misalignment is between the block and the bell housing.

Question 24Clutch

On a two-plate clutch with an intermediate plate, which condition would cause drag even with full pedal travel and correct free play?

  1. A diaphragm spring that has lost clamp load
  2. A sticking intermediate plate or dry input shaft splines Correct answer.
  3. Friction facings glazed from overheating
  4. A release bearing that is worn and noisy

Explanation

Multi-plate clutches need the intermediate plate to float on its drive lugs and the discs to slide freely on the input shaft splines. If either binds, the discs stay in contact with the flywheel and intermediate plate when the pedal is down, and the clutch drags. A worn bearing, glazed facings, or a weak spring would cause noise or slip rather than a failure to separate.

Question 25Clutch

When specifying a replacement clutch for a heavy truck, the clutch torque rating should be:

  1. Equal to transmission capacity divided by the axle ratio
  2. Based mainly on the vehicle's gross weight rating
  3. At or above the engine's peak torque with a safety margin Correct answer.
  4. As low as possible to reduce pedal effort

Explanation

A clutch must carry the engine's peak torque plus a margin for wear, heat, and heavy-load launches, so its rating should be at or above peak engine torque. Rating by transmission capacity, axle ratio, vehicle weight, or pedal effort alone can leave the clutch undersized and slipping.

Question 26Clutch

What is the primary function of the clutch release bearing in a manual truck clutch?

  1. To keep the clutch disc centered on the flywheel
  2. To dampen torsional vibration between the engine and transmission
  3. To apply axial force to the pressure plate release mechanism Correct answer.
  4. To multiply engine torque before it reaches the transmission

Explanation

The release bearing is a thrust bearing. When the pedal is depressed, the fork pushes it against the rotating pressure plate release mechanism, applying axial force that removes clamp load from the disc. It does not center the disc or damp torque.

Question 27Clutch

A pilot bearing or bushing is installed in the end of the crankshaft on a manual transmission truck. What is its purpose?

  1. To support the rear of the crankshaft under load
  2. To seal the transmission input shaft against oil leakage
  3. To provide a replaceable wear surface for the clutch release fork
  4. To center and support the front of the transmission input shaft Correct answer.

Explanation

The pilot bearing or bushing is pressed into the crankshaft flange and supports the forward end of the transmission input shaft. It keeps the shaft aligned with the crankshaft centerline so the disc hub and splines run true. A worn pilot bearing can cause noise, drag, or input shaft misalignment.

Question 28Clutch

What is the purpose of a clutch alignment tool during clutch installation?

  1. To set the release bearing clearance to specification
  2. To center the disc while the pressure plate is tightened Correct answer.
  3. To check flywheel runout before bolting the pressure plate
  4. To measure the installed height of the diaphragm spring fingers

Explanation

The alignment tool holds the disc hub centered on the flywheel and pilot bore while the pressure plate bolts are tightened. If the disc is off-center, the input shaft may not enter the splines and the clutch can drag.

Question 29Clutch

A clutch disc is removed for inspection, and the rivet heads are flush with the friction lining surface. What does this indicate?

  1. The lining is worn out and the disc must be replaced Correct answer.
  2. The disc has normal wear and can be reused
  3. The disc hub splines are worn and need lubrication
  4. The disc has been contaminated with oil and should be cleaned

Explanation

Rivets flush with the lining mean the friction material has worn to its service limit, so the disc cannot be reused. Oil contamination and spline wear are separate inspection points that also affect reuse.

Question 30Clutch

A clutch is replaced, but the bell housing face runout is measured at 0.015 in (0.38 mm) while the specification is 0.008 in (0.20 mm). What is the most likely result if the truck is put into service?

  1. Faster clutch brake wear because the brake is applied too early
  2. Uneven release and chatter from misalignment of the clutch assembly Correct answer.
  3. Higher engine idle speed because the flywheel sensor gap has changed
  4. A lower clutch pedal effort because the release bearing is preloaded

Explanation

Bell housing face runout tilts the transmission centerline relative to the crankshaft. The disc then runs off-center, causing uneven release, drag, and chatter. The housing must be corrected with offset dowels or replaced.

Question 31Clutch

A hydraulic clutch pedal gradually sinks to the floor when held down, but no external fluid leak is found. Which cause is most likely?

  1. A clutch disc that is worn beyond specification
  2. Air trapped in the release bearing grease
  3. An internal leak past the master cylinder piston seal Correct answer.
  4. A broken return spring on the release fork

Explanation

A master cylinder cup seal that bypasses internally lets fluid return to the reservoir while the pedal is held, so the pedal sinks with no visible leak. A worn disc, air in the system, or a broken return spring would not produce this slow sink with no external loss.

Question 32Clutch

Worn bushings in a mechanical clutch linkage cause lost motion. What effect does this have on clutch operation?

  1. Less pedal travel reaches the release mechanism, causing drag Correct answer.
  2. The clutch will engage more gradually and slip less
  3. The clutch brake will apply whenever the pedal is partly depressed
  4. The release bearing will retract farther from the pressure plate

Explanation

Lost motion from worn bushings uses up pedal travel before the release bearing moves. The remaining travel may be insufficient to fully release the clutch, causing drag and hard shifting.

Question 33Clutch

Why should the clutch brake on a heavy truck be applied only when the vehicle is stopped?

  1. It prevents the transmission from engaging first gear when cold
  2. It allows the driver to downshift without using the throttle
  3. It increases release bearing life by keeping the bearing loaded
  4. It will overheat and wear rapidly if used while moving Correct answer.

Explanation

The clutch brake is a friction device that stops the transmission input shaft so a gear can be engaged from neutral. It is designed for standstill use only; applying it while moving generates heat and rapid wear.

Question 34Clutch

The release fingers on a coil-spring pressure plate are uneven in height. What is the most likely effect?

  1. The clutch will hold more torque because clamp load increases
  2. The clutch will release unevenly and may drag or chatter Correct answer.
  3. The clutch brake will release sooner during pedal travel
  4. The pedal will become lighter as the disc wears

Explanation

Uneven release finger height means the release bearing contacts some fingers before others. The pressure plate tilts, so clamp load is removed unevenly and the disc may drag or chatter.

Question 35Clutch

What is the function of the cushion (marcel) springs between the clutch disc facings?

  1. To increase the total friction area of the clutch disc
  2. To keep the release bearing in constant contact with the pressure plate
  3. To absorb engine torque spikes before they reach the transmission
  4. To provide a slight spring action that smooths clutch engagement Correct answer.

Explanation

Cushion or marcel springs are wavy metal separators between the facings that compress slightly as the clutch engages. They provide progressive clamp load, reducing chatter and shock. Damper springs in the hub handle torque fluctuations.

Question 36Clutch

A clutch disc is marked "FLYWHEEL SIDE." What can happen if the disc is installed backward?

  1. The clutch brake will apply during normal upshifts
  2. The clutch will slip because clamp load is reduced
  3. The hub may hit the flywheel bolts and prevent engagement Correct answer.
  4. The release bearing will not contact the pressure plate

Explanation

The disc hub is offset, and the flywheel-side marking must face the flywheel. Reversing it can make the hub or damper springs contact the flywheel bolts and hold the disc away from the flywheel, causing drag or no engagement.

Question 37Clutch

How should the bolts that attach a clutch pressure plate to the flywheel be tightened?

  1. Tighten evenly and gradually in a crisscross pattern to the specified torque Correct answer.
  2. Tighten with the release bearing fully loaded to center the plate
  3. Tighten all the way, one bolt at a time, working clockwise
  4. Tighten only until the pressure plate contacts the flywheel

Explanation

Pressure plate bolts must be drawn down evenly and gradually in a crisscross pattern to avoid distorting the cover and diaphragm spring. Final torque should follow the manufacturer's sequence.

Question 38Clutch

A flywheel housing bore is being checked for concentricity with the crankshaft. Where should the dial indicator be positioned?

  1. On the release fork pivot, with the indicator mounted on the frame
  2. On the flywheel friction surface, with the indicator mounted on the bell housing
  3. On the transmission input shaft, with the indicator mounted on the output shaft
  4. On the housing bore, with the indicator mounted on the crankshaft Correct answer.

Explanation

Concentricity of the flywheel housing bore is checked with the indicator base on the crankshaft and the stylus on the bore. This measures whether the transmission centerline aligns with the crankshaft; excessive eccentricity causes clutch misalignment.

Question 39Clutch

A technician replaces a clutch master cylinder with one that has a larger bore but the same stroke and pedal ratio. What is the effect?

  1. Pedal effort decreases and pedal travel increases
  2. Pedal effort increases and pedal travel decreases Correct answer.
  3. Both pedal effort and pedal travel increase
  4. Pedal effort and travel remain unchanged if the fluid is bled

Explanation

A larger master cylinder bore displaces more fluid per unit of pedal stroke, so the slave moves farther and less pedal travel is needed. However, for the same pedal force the hydraulic pressure is lower, so pedal effort rises.

Question 40Clutch

A release fork has a worn pivot ball, changing the effective lever ratio. Which symptom is most likely?

  1. Release bearing travel is reduced, so the clutch may drag Correct answer.
  2. The clutch engages sooner and the pedal feels lighter
  3. The clutch brake applies with less pedal travel
  4. The pressure plate clamp load increases, causing rapid disc wear

Explanation

The release fork pivot is the fulcrum that transfers pedal travel to the release bearing. A worn pivot changes the lever ratio and can reduce bearing travel, leaving the clutch partially engaged and dragging. It may also make the pedal feel loose or change the clutch brake point.

Question 41Transmission (manual and automatic)

In a manual transmission, what is the primary purpose of the synchronizer assembly?

  1. multiply engine torque during acceleration
  2. lock the mainshaft to the countershaft
  3. equalize gear and shaft speeds Correct answer.
  4. provide a neutral detent for the shift lever

Explanation

A synchronizer uses a cone clutch to bring the engaging gear and the synchronizer sleeve to the same speed. This prevents gear clash and allows the dog teeth to mesh. Torque multiplication and neutral detents are handled by other components.

Question 42Transmission (manual and automatic)

In a typical constant-mesh manual transmission, the countershaft is driven by:

  1. the reverse idler gear on its shaft
  2. the output shaft companion flange and yoke
  3. the clutch disc hub through a splined coupling
  4. the input shaft main drive gear Correct answer.

Explanation

The input shaft carries a main drive gear that meshes with the countershaft drive gear. Engine torque enters the countershaft, travels through the countershaft gears, and returns to the mainshaft in the selected ratio. The output shaft is driven by the mainshaft, not the other way around.

Question 43Transmission (manual and automatic)

A torque converter multiplies engine torque most effectively when:

  1. turbine speed is nearly equal to impeller speed under cruise
  2. a large speed difference between impeller and turbine Correct answer.
  3. transmission fluid is at normal operating temperature
  4. the converter clutch is fully applied

Explanation

Torque multiplication depends on the speed difference, or slip, between the impeller and turbine. It is greatest at stall and decreases as turbine speed approaches impeller speed. Once speeds are close, the converter clutch may apply to eliminate slip.

Question 44Transmission (manual and automatic)

What component holds the vehicle when an automatic transmission is placed in Park?

  1. the converter lockup clutch and damper
  2. the forward clutch pack and apply piston
  3. the low/reverse band and hydraulic servo
  4. a mechanical park pawl Correct answer.

Explanation

Park uses a mechanical pawl that drops into a tooth on the output shaft or park gear. A spring and cam mechanism engage the pawl, and the pawl is strong enough to hold the vehicle. Hydraulic clutches and bands are not applied to hold the vehicle in Park.

Question 45Transmission (manual and automatic)

A shift fork in a manual transmission is used to:

  1. support the mainshaft rear bearing
  2. drive the speedometer driven gear
  3. apply the clutch release bearing
  4. slide the synchronizer sleeve Correct answer.

Explanation

The shift fork fits into a groove on the synchronizer sleeve and slides it toward the selected gear. This engages the synchronizer and locks the gear to the mainshaft. Bearings, speedometer gears, and the clutch release mechanism are separate components.

Question 46Transmission (manual and automatic)

A power take-off (PTO) on a truck transmission typically:

  1. drives auxiliary equipment from transmission gearing Correct answer.
  2. cools the transmission fluid during heavy load
  3. replaces the transmission countershaft
  4. disconnects the driveline during gear shifts

Explanation

A PTO is an auxiliary gearbox or drive opening that takes power from the transmission, often through a countershaft gear. It drives equipment such as hydraulic pumps, winches, or blowers. It does not replace internal transmission parts or cool the fluid.

Question 47Transmission (manual and automatic)

On many automatic transmissions, fluid level is checked with the engine running and the transmission in Park because:

  1. the fluid expands only when the engine is running
  2. the valve body drains when the engine is off
  3. the pump is operating and the converter filled Correct answer.
  4. the park pawl locks the torque converter

Explanation

With the engine running, the transmission pump circulates fluid and keeps the torque converter and cooler circuits filled. Checking in Park with the engine running gives a representative level. Fluid expansion is mainly temperature-related, and the park pawl does not lock the converter.

Question 48Transmission (manual and automatic)

In a manual transmission, reverse gear typically uses:

  1. a one-way clutch and sprag
  2. a planetary gearset with a sun gear
  3. an idler gear for direction Correct answer.
  4. a triple-cone synchronizer assembly

Explanation

Reverse usually adds an idler gear between the countershaft and mainshaft so the output turns opposite to the input. Many heavy truck transmissions use a sliding or non-synchronized reverse gear. Planetary gearsets and one-way clutches are typical of automatic transmissions.

Question 49Transmission (manual and automatic)

During a shift, the blocking ring prevents gear engagement until:

  1. the clutch pedal is fully released
  2. the countershaft has stopped rotating
  3. the shift lever has moved through the neutral gate
  4. the cone clutch has equalized gear and sleeve speeds Correct answer.

Explanation

The blocking ring indexes against the gear cone and blocks the sleeve until friction has equalized speeds. Once speeds match, the ring can index and the sleeve slides over the dog teeth. Moving through neutral or releasing the clutch does not by itself synchronize the gear.

Question 50Transmission (manual and automatic)

When a manual transmission is in direct drive, power flows:

  1. input shaft locked to mainshaft Correct answer.
  2. through a planetary gearset
  3. through the countershaft gears and bearings
  4. through the reverse idler gear train

Explanation

In direct drive, the input shaft and mainshaft are locked together, so the output turns at engine speed. Torque does not pass through the countershaft gears in this mode. Countershaft gears are used for the reduction ratios and reverse.