ch 15

Which of the following gear ratios increases transmission output shaft speed the most?

(d)0.73:1

What is the typical air pressure regulator specification for the pneumatics on a Roadranger com- pound truck transmission?

60 psi

An auxiliary mechanical drive for truck accessories driven by the transmission is known as a(n):

b. power take-off (PTO) unit

Which of the following components in a typical heavy-duty, twin-countershaft transmission could be described as floating?

b. the main shaft

Which of the following is the most widely used standard transmission geartrain arrangement in heavy-duty trucks?

b. twin countershaft

Which type of transmission requires double-clutching between shifts?

b. nonsynchronized

What is the gear pitch in the illustration

B. 7

What is NOT an advantage of helical gears

C. Reduced thrust forces

What is the function of synchronizers in a truck transmission?

a. Bring the rotational speed of two rotating components to a single speed b. Lock two rotating components together c. Reduce gear lashing d.) All of the above

What component retains a shift rail in position following a shift?

a. a detent ball

In a range shift air control system, which component distributes inlet air pressure to both the low- and high-range air hoses running to the range cylinder?

a. a slave valve

Which type of gear is more likely to develop gear whine at higher speeds?

a. a spur gear

When an idler gear is placed between the driving and driven gear, the driven gear:

a. rotates in the same direction as the driving gear

The component used to ensure that the main shaft and the main shaft gear about to be locked to it are rotating at the same speed is known as a:

a. synchronizer

Which of the following gear ratios indicates the most amount of overdrive?

d. 0.64:1

Which of the following is true of a twin-countershaft standard transmission?

d. All of the above a. It divides input torque between two separate shafts. b. It allows the face width of each gear to be reduced. c. It allows the main shaft to float between the countershafts.

Which of the following statements is true regarding the function of a transfer case?

d. All of the above a. It transfers torque from the transmission to a front drive axle. b. It transfers torque from the transmission to the rear drive axle(s). c. It may provide an additional gear reduction in the drivetrain.

When sliding gearshift mechanisms are used, which gears do they control?

d. All of the above a. high and low gears in the auxiliary section b. first and reverse gears in the main box c. direct and overdrive gears in the auxiliary section

Which of the following statements is/are correct about geartrains?

d. All of the above. a. They transmit speed and torque unchanged. b. They decrease speed and increase torque. c. They increase speed and decrease torque.

To provide for overdrive gearing in the high- and low-auxiliary transmission ranges, which of the following components is added to the basic range-shift air control system?

d. both a and b a. a splitter cylinder b. a button-actuated shift lever valve