401dB Transmission Fundamentals - Part B

Question 1

In most twin countershaft transmissions, which of the following does the auxiliary section not provide?

a) reverse gearing
b) range gearing
c) splitter gearing
d) deep reduction gearing

Answer 1

a) reverse gearing

Question 2

The auxiliary drive gear receives torque from the auxiliary countershafts.
T/F

Answer 2

false; The auxiliary drive gear receives torque from the mainshaft.

Question 3

The auxiliary section uses the synchronizer to aid in the:

Answer 3

b) range shift.

Question 4

The purpose of the range, splitter and deep reduction cylinders is to:

a) transmit the gearshift lever actions to shift the auxiliary section sliding clutches.
b) use the air signal to shift the main section sliding clutches.
c) use the air signal to shift the auxiliary section sliding gears.
d) use the air signal to shift the auxiliary section sliding clutches.

Answer 4

d) use the air signal to shift the auxiliary section sliding clutches.

Question 5

The output shaft:

a) delivers torque to the driveline.
b) is supported on tapered roller bearings.
c) is splined to the synchronizer sliding clutch.
d) all of the above.

Answer 5

d) all of the above.

Question 6

The two-speed auxiliary section provides:

a) reduction and direct.
b) reduction and overdrive.
c) direct and overdrive.
d) direct and neutral.

Answer 6

a) reduction and direct.

Question 7

The three-speed auxiliary section provides:

a) 15 usable gears.
b) 18 usable gears.
c) 13 usable gears.
d) 12 usable gears.

Answer 7

d) 12 usable gears.

Question 8

Which position provides direct drive in the four-speed auxiliary section?

a) low range, low splitter
b) low range, high splitter
c) high range, low splitter
d) high range, high splitter

Answer 8

d) high range, high splitter

Question 9

Identify the two (2) methods of lubrication used on multiple countershaft transmissions.

Answer 9

a) splash

b) pressure

Question 10

When a spin-on type of oil filter is used on a transmission lubrication system, the filter is located between the oil cooler and the:

Answer 10

b) pump outlet port.

Question 11

Transmissions that utilize splash lubrication generally filter their oil by means of:

Answer 11

magnetic drain plugs or magnets located in the bottom of the case.

Question 12

How should you check the oil level of the transmission?

Answer 12

Always check the transmission lubricant level with the vehicle on a level surface, front-to-rear and side-to-side. Clean the area around the filler plug and ensure that the oil is level with the lower edge of the filler plug opening.

Question 13

Which of the following best defines a hybrid drive vehicle?

a) any vehicle that has two or more drive axles
b) any vehicle that has two or more methods of propulsion
c) any vehicle that has two or more electrical systems
d) any vehicle that is propelled using hydraulics

Answer 13

b) any vehicle that has two or more methods of propulsion

Question 14

Explain the difference between a series hybrid and a parallel hybrid.

Answer 14

In a series hybrid the engine never directly propels the vehicle. In a parallel hybrid an electric motor or hydraulic motor is sandwiched between the engine and the transmission assists with the propulsion of the vehicle.

Question 15

Identify the three (3) key components of a diesel parallel electric hybrid.

Answer 15

• motor/generator
• inverter
• power electronics carrier (PEC)

Question 16

What are the two (2) primary functions of the motor generator?

Answer 16

• to propel the vehicle

- to charge the battery pack

Question 17

Why are lithium ion batteries desirable for electric hybrid applications?

Answer 17

low discharge rates and high storage capacity

Question 18

During diesel electric propel mode, what effect does the electric assist that the motor provides have on the diesel engine?

a) lowers engine duty cycle
b) increases engine duty cycle
c) increases the engine’s fuel consumption
d) lowers the engine RPM

Answer 18

lowers engine duty cycle

Question 19

What effect does coasting or braking have on the lithium ion batteries?

Answer 19

the batteries are charged

Question 20

In a diesel hydraulic hybrid assembly which component receives energy from the engine or the rear axle?

Answer 20

transfer case

Question 21

Explain the two (2) functions of the hydraulic pump/motor.

Answer 21

The hydraulic pump/motor has two functions.

• During coast or regenerative braking it provides the oil flow into the accumulator to pressurize the system.
• During propel mode the flow of oil is reversed and the pump acts as a hydraulic motor to apply torque to the drive line.

Question 22

Explain the function of the accumulator in a diesel hydraulic hybrid vehicle.

Answer 22

The function of the accumulator is to store energy for the hydraulic launch system.

Question 23

During propulsion, explain the function of the accumulator, hydraulic motor and transfer case.

Answer 23

Oil flows from the high pressure accumulator to the pump/motor. The oil causes the pump/motor to operate as a motor. The motor transfers the fluid energy to the transfer case, which converts the fluid energy into mechanical energy. The transfer case applies torque to the drive line to assist with the propulsion of the vehicle.

Question 24

In a diesel electric hybrid, what color are the high voltage cables?

Answer 24

orange

Question 25

In a diesel hydraulic hybrid, what is the minimum amount of time to wait for the accumulator to drain after shut down?

Answer 25

5 minutes