Transfer Case and Auxiliary Drives

Question 1

On a short wheel based vehicle, what drivetrain equipment is used to drive the front driving axle?

a. transfer case
b. a special inter-axle differential assembly
c. a transmission with front and rear outputs
d. a gear system off of the front of the engine

Answer 1

b. a special inter-axle differential assembly

Question 2

What type of lubrication do transfer cases utilize?

Answer 2

The internal transfer case components are generally lubricated by a splash type of lubrication system. Many transfer cases are also equipped with a positive displacement oil pump as part of the lubrication system.

Question 3

The mechanism that gives the operator the ability to disengage the torque to the front drive axle is called the:

a. axle seperator
b. limiting clutch
c. front splitter
d. front axle declutch

Answer 3

d. front axle declutch

Question 4

What device does a full time transfer case use to prevent driveline windup?

a. planetary gear set
b. typical differential assembly
c. limited slip clutch pack
d. windup clutch

Answer 4

a. planetary gear set

Question 5

Explain the procedure used to check the oil level in the transfer case:

Answer 5

To check the oil level, clean the dirt away from the area surrounding the filler plug to prevent the accidental contamination while checking the level. The oil must be level with the bottom of the filler plug opening.

Question 6

Excessive noise and vibration from the transfer case can be caused by:

a. excessive driveline angles
b. excessive transfer case bearing endplay.
c. operating on good surface with declutch engaged.
d. all of the above.

Answer 6

d. all of the above

Question 7

One of the vital concerns with the transfer case assembly is:

a. housing concentricity
b. input shaft timing
c. output shaft timing
d. bearing endplay

Answer 7

d. bearing endplay

Question 8

What must the operator do before engaging the power takeoff?

a. shut the engine off
b. stop the transmission countershaft from turning
c. first engage the component that the power takeoff is powering.
d. raise the engine to governed rpm

Answer 8

b. stop the transmission countershaft from turning.

Question 9

The indicator light for the power takeoff system is activated by an engagement switch located in the shift valve.
True
False

Answer 9

False

Mounted in the shift cover

Question 10

What 2 functions do the gaskets between the power takeoff and the transmission provide?

Answer 10

a. Act as a seal to keep lubrication from leaking between the two mating surfaces.
b. Provide a way of setting the proper backlash between the PTO input gear and the PTO drive gear of the transmission.

Question 11

When installing an adaptor housing, it is only necessary to adjust the gear backlash between the adaptor housing and the transmission drive gear.
True
False

Answer 11

False
Check gear backlash as part of the installation process. Do not assume that the proper backlash will be obtained by installing the same number and thickness of gaskets that were originally on the vehicle.

Question 12

When installing the repaired power takeoff, it is acceptable to install it without measuring backlash if the same number and thickness of gaskets that were originally removed are used.
True
False

Answer 12

False

Question 13

State the function of the transfer case:

Answer 13

The transfer case receives torque from the main or auxiliary transmission. It then passes that torque on to the rear driving axles and forward to the front driving axle.

Question 14

Transfer cases are only available in one configuration with an option to disengage the drive to the front axle.
True
False

Answer 14

False

Question 15

On a transfer case with more than one range option, high range is typically an overdrive.
True
False

Answer 15

False

Question 16

A transfer case mounted power takeoff cannot receive more torque than the engine can develop.
True
False

Answer 16

False

Question 17

What could cause oil to be lost out of the breather?

Answer 17

If either the range shift cylinder, front axle declutch cylinder or the power takeoff shift cylinder o-rings are leaking, the housing is put under excessive pressure.
The rapid air venting can cause airborne oil particles to be pulled out the breather.

Question 18

When removing the transfer case, it is critical that the mounting location of the drivelines be clearly marked.
True
False

Answer 18

True

Question 19

Which types of auxiliary drive systems are always driving any time the engine is turning?
A. front engine mounted
B. rear engine mounted
C. transfer case mounted
D. drop box
E. auxiliary transmission mounted
F. transmission mounted power takeoff

Answer 19

A. front engine mounted

B. rear engine mounted

Question 20

On the air actuated power takeoff system, what is the air routed through before going to the air valve?
A. pressure protection valve.
B. Pressure regulator valve.
C. flow control valve
D. the shift cylinder

Answer 20

A. Pressure protection valve

Question 21

What precautions must be taken to properly match a power takeoff to an application and prevent equipment damage?

Answer 21

A. Always refer to the appropriate catalogue, service literature and owners manuals. Follow the manufacturers recommendations when selecting, installing, repairing or operating a PTO.
B. Never attempt to use a PTO that is not specifically recommended by the PTO manufacturer for the vehicle transmission.
C. Always match the PTO’s specified output capabilities with the requirements of the equipment to be powered.
D. Never use a power takeoff whose speed range could exceed the maximum safe operating speed of the equipment to be powered.

Question 22

PTO backlash must be measured between:

a. the PTO input gear and the PTO output gear.
b. the PTO input gear and the idler.
c. the PTO input gear and the transmission drive gear.
d. the transmission drive gear and the transmission input gear.

Answer 22

c. the PTO input gear and the transmission drive gear.

Question 23

If the power takeoff is installed with insufficient backlash, the complaint will be:

a. gear clatter.
b. gear whine.
c. sheared keys.
d. housing breakage.

Answer 23

b. gear whine.