Question 1

Technician A says that slow range shifts may be caused by dry (insufficient silicone lube)O-rings.Technician B says that slow range shifts can be caused by excessive silicone lube applied to O-rings.Who is correct?

Accepted Answer

Both technicians are correct. Dry O-rings can cause slow range shifts due to increased friction and poor sealing, while excessive silicone lube can attract dirt and debris or cause hydraulic control issues, also leading to slow shifts.

Question 2

When troubleshooting the source of a transmission leaking oil from both the front and rear seals,which of the following should be checked out first?

Accepted Answer

A plugged breather can cause pressure to build up inside the transmission housing, leading to oil being forced out of both the front and rear seals.

Question 3

Technician A says that splitter slip-out often occurs when using the clutch on upshifts.Technician B says that splitter slip-out can be caused by pre-selecting splitter shifts.Who is correct?

Accepted Answer

The answer of Technician A says that splitter slip-out often...

Question 4

Which of the following problems would be more likely to cause a twisted mainshaft?

Accepted Answer

Starting in too high a gear ratio can put excessive stress on the mainshaft, potentially causing it to twist due to the increased torque demand.

Question 5

When a transmission is removed from a heavy duty truck,the input shaft is observed to be extremely worn.Technician A says that the engine flywheel housing concentricity should be (dial)indicated.Technician B says that the engine mounts should be checked.Who is correct?

Accepted Answer

Both technicians are correct. Technician A suggests checking the engine flywheel housing concentricity to ensure it's properly aligned, as misalignment can cause excessive wear on the input shaft. Technician B recommends checking the engine mounts because if they are worn or improperly installed, they can lead to misalignment between the engine and transmission, causing similar wear issues.

Question 6

Technician A says that hard shifts could be the result of sheared-off clutch brake tangs.Technician B says that when clutch brake tangs shear,the clutch brake is forced to rotate with the transmission input shaft? Who is correct?

Accepted Answer

The answer of Technician A says that hard shifts could...

Question 7

Technician A says that a fracture in the auxiliary section housing could be caused by seized clutch release bearing.Technician B says that a fracture in the auxiliary section housing could be caused by a driveline misalignment problem.Who is correct?

Accepted Answer

A fracture in the auxiliary section housing is more likely to be caused by a driveline misalignment problem, as it can create stress and lead to fractures. A seized clutch release bearing typically affects clutch operation rather than causing housing fractures.

Question 8

Technician A says that a transmission output yoke retaining nut can be final torqued using a 1-inch drive shop air gun.Technician B says that the same nut can be safely removed using a 1-inch drive shop air gun.Who is correct?

Accepted Answer

Technician B is correct because a 1-inch drive shop air gun can safely remove a transmission output yoke retaining nut due to its high torque output. However, final torquing should be done with a torque wrench to ensure the nut is tightened to the manufacturer's specifications, which is why Technician A's statement is incorrect.

Question 9

Technician A says that a new transmission filled with Eaton E-500 lubricant does not require an initial break-in drain and fill after the first 3,000 to 5,000 miles of service.Technician B says that E-250 lubricant is rated for service intervals of up to 250,000 linehaul miles.Who is correct?

Accepted Answer

Eaton E-500 lubricant does not require an initial break-in drain and fill, and E-250 lubricant is rated for service intervals of up to 250,000 linehaul miles.

Question 10

When installing a shift bar (rail)housing,how should the 3 rails be positioned?

Accepted Answer

When installing a shift bar (rail) housing, all three rails should be positioned in the neutral position. This ensures that the transmission is in a neutral state, allowing for the proper alignment and installation of the shift bar housing without engaging any gears.

Question 11

What would be the result of engaging two sliding clutches at the same time during the assembly of a twin-countershaft truck transmission?

Accepted Answer

Engaging two sliding clutches simultaneously in a twin-countershaft truck transmission would lock both the countershafts and the mainshaft, preventing any of them from rotating. This is because the clutches would attempt to engage gears that are meant to rotate at different speeds or in different directions, causing a mechanical lock-up.

Question 12

Technician A says that when range slipout occurs,the transmission air pressure regulator may require adjustment.Technician B says that range slipout can be caused by a leaking air hose.Who is correct?

Accepted Answer

The answer of Technician A says that when range slipout...

Question 13

If a gear shift lever on a COE truck chassis jams in gear,which of the following would be the most likely cause?

Accepted Answer

Improper linkage adjustment is the most likely cause for a gear shift lever jamming in gear, as it directly affects the movement and alignment of the gear shift mechanism.

Question 14

When a yoke seal race is damaged,which of the following is the cost-effective repair method?

Accepted Answer

Resleeving with a wear ring is a cost-effective method for repairing a damaged yoke seal race, as it allows the original component to be reused rather than replaced.

Question 15

Technician A says that some bolt holes used to couple flanges and manifolds to the transmission,bore through the housing and can potentially leak oil.Technician B says that thread sealant should be used on fasteners used to couple flanges and manifolds to transmissions.Who is correct?

Accepted Answer

Technician A is correct because some bolt holes indeed go through the housing and can leak oil if not properly sealed. Technician B is correct because using thread sealant on these fasteners can prevent oil leaks by sealing the threads that might otherwise allow oil to escape.

Question 16

Technician A says that it is usual to mark two adjacent gear teeth on a countershaft gear for timing purposes.Technician B says that it is usual to mark a single mainshaft gear tooth for timing purposes.Who is correct?

Accepted Answer

Marking gear teeth for timing purposes typically involves marking specific teeth on both gears that mesh together, not just on a countershaft or mainshaft gear individually.

Question 17

Technician A says that gear jump-out that always occurs in one main box ratio can be caused by a broken detent spring.Technician B says that a driver that complains of gear jump-out in all main box ratios,may be shifting without disengaging the clutch.Who is correct?

Accepted Answer

Technician A is correct because a broken detent spring can indeed cause gear jump-out in a specific gear by failing to securely hold the gear in place. Technician B is also correct because not fully disengaging the clutch during shifting can lead to gear jump-out across all gears due to incomplete gear engagement.

Question 18

Technician A says that a no range shift condition could be caused by cracked slave valve piston.Technician B says that to repair a cracked range shift piston,the compound (auxiliary section)must be removed.Who is correct?

Accepted Answer

The answer of Technician A says that a no range...

Question 19

When heating a bearing prior to installation,which of the following is the recommended method of ensuring that it is not over-heated?

Accepted Answer

Using a hot plate and Tempilstick is the recommended method for heating a bearing prior to installation to ensure it is not overheated. The Tempilstick provides a precise indication when the bearing reaches the target temperature.

Question 20

Which of the following driver related conditions would be more likely to result in a twisted input shaft?

Accepted Answer

Not using the clutch to shift can lead to a twisted input shaft because it causes undue stress on the transmission components due to the lack of smooth engagement and disengagement between the engine and the transmission.

Quiz 16: Standard Transmission Servicing

Technician A says that slow range shifts may be caused by dry (insufficient silicone lube) O-rings.Technician B says that slow range shifts can be caused by excessive silicone lube applied to O-rings.Who is correct?