1. The driver of a truck says he hears a grinding noise
when the transmission is in neutral and the truck is
stopped; but the noise goes away when the clutch
pedal is depressed. Which of these could be the
cause?
A. worn pilot bearing
B. worn input shaft bearing
C. worn clutch release (throw...
ASE T3 (100% Verified)
1. The driver of a truck says he hears a grinding noise
when the transmission is in neutral and the truck is
stopped; but the noise goes away when the clutch
pedal is depressed. Which of these could be the
cause?
A. worn pilot bearing
B. worn input shaft bearing
C. worn clutch release (throwout) bearing
D. worn auxiliary transmission countershaft bearing correct answers 1. The correct answer is B. The noise
occurs only when the input shaft is rotating. The bearing handles the relative motion between shaft and
case and thus works only when the shaft is moving. This occurs when the truck isidling with the clutch
engaged. The noise goes away when the clutch pedal is depressed because the input shaft then stops
turning and the bearing is stationary. The other symptoms would only occur when either the clutch is
engaged or when the transmission is being shifted.
2. A manual shift transmission slips out of fifth gear. The MOST likely cause of this problem is:
A. a broken detent spring
B. too much shaft and gear spline wear
C. worn countershaft bearings
D. a chipped countershaft drive gear correct answers 2. The correct answer is A. The detent ball lightly
holds the gear lever in place when a shift is complete. With a broken spring, there will be no pressure
holding the ball in the detent located in the shift rail. Vibration can easily cause the direct drive (top gear)
shift collar to slide and disengage. Answers B and D would cause grinding when shifting into gear, while
answer C would cause a whining noise.
3. The shift lever on a single countershaft transmission is hard to move. Which of these is the MOST
likely cause?
A. bent shift rails
B. galled sliding clutch gears
C. worn detent springs
D. too much mainshaft gear end-play correct answers 3. The correct answer is B. Galled surfaces on the
sliding clutches would make it difficult for them to slide along the shafts and in and out of the gears. Bent
shift rails and worn detent springs would cause the transmission to slip out of gear. Too much mainshaft
,gear end play would cause shifting to be next to impossible and the transmission will exhibit a growling
noise.
4. In a transmission that has been taken apart, all of the bearings are excessively worn. Technician A says
the cause could be moisture in the lubricant. Technician B says the cause could be too high an operating
temperature. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B correct answers 4. The correct answer is C, both technicians are right. Bearing wear
often occurs when the viscosity of the gear lube is too low. Water dilutes the gear lube, thereby thinning
it. Heat also thins the gear lube by breaking it down chemically.
5. A truck with a high-torque, low-rpm engine exhibits a great deal of gear noise, as well as wear of the
splines on various drivetrain parts. The truck uses a rigid disc clutch. All the U-joint angles are
acceptable. The MOST likely cause of this problem is that the
A Driver abuses the clutch by releasing it too rapidly
B. Engine produces torsional vibration, which should be removed from the drivetrain by using a
dampened disc clutch.
C. Engine mounts are worn.
D. Engine rating is such that the transmission requires the use of an oil cooler. correct answers 5. The
correct answer is B. A rigid clutch cannot dampen the severe vibrations produced by modern high torque
diesels. The only other source of the kind of vibration torque that would cause such damage would be
misaligned driveshafts, and they have been found to be OK.
6. A truck fleet presently uses transmissions with an overdrive top gear ratio. It wishes to convert its
trucks to the use of direct-drive transmissions. In order to get approximately the same number of engine
revolutions per mile in top gear, the company would have to:
A convert the gearing in its rear axles to a higher (numerical) ratio
B. convert the gearing in its rear axles to a lower (numerical) ratio
C. it need not convert (the same rear axle ratio will produce the same engine revolutions per mile)
D. convert to lower-profile tires (which would turn more revolutions per mile) correct answers 6. The
correct answer is B. On vehicles with overdrive. the engine turns more slowly than the transmission out
put shaft and the driveshafts at any given speed. With a direct drive transmission, the engine must turn at
the same speed as the driveshafts-in other words, with the same axle, faster. A numerically lower axle,
, requiring fewer revolutions of the driveshafts, would be the only means of bringing the required rpm of
engine and drive shafts back down.
7. Which one of the following operating conditions does NOT indicate to the technician that the truck
would operate more reliably with a transmission oil cooler?
A. truck is rated at 350 hp
B. truck has a power rating of 450 hp
C. truck cab has the maximum number of aerodynamic devices to smooth air flow
D. truck normally cruises in an overdrive ratio of 0.85:1 correct answers 7. The correct answer is A. Any
truck rated less than 400 hp is normally approved for operation without a transmission oil cooler; only
trucks of 400 hp and up require them.
8. A hydraulic clutch slave cylinder is being replaced. What should the technician do first?
A. disconnect the clutch pedal pushrod
B. remove the slave cylinder from its mounting
C. disconnect the hydraulic line
D. adjust clutch pedal free-play correct answers 8. The correct answer is A. The clutch pedal pushrod
must be disconnected before servicing the slave cylinder. Damage to the master cylinder can occur if the
pedal is accidentally depressed with the slave cylinder disconnected.
9. A 13-speed transmission exhibits wear problems in two places: the shift fork located on the yoke bar
that shifts the splitter, and the surfaces of the shift collar that the fork bears against. The MOST likely
problem is:
A. a bad air seal in the overdrive shift unit
B. engagement of overdrive while the transmission
is in low range
C. the driver preselects the splitter button, fip-
ping it and then failing to complete the shift until
some time later
D. transmission lube oil diluted with water correct answers 9. The correct answer is C. Flipping the
splitter button applies air pressure to the mechanism, causing the shifting fork to apply pressure to the
gear. The pressure continues until the driver depresses the clutch or appropriately changes throttle
position and allows the transmission to shift.
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