Question 1

Technician A says the output of the gear set will be in the opposite direction to the input, which produces reverse gear when the planetary carrier is held. Technician B says the gearset produces a gear reduction when the planetary carrier is the input member. Who is correct?

Accepted Answer

Technician A is correct as the output of the gear set is in the opposite direction when the planetary carrier is held, which is necessary to produce reverse gear. Technician B is also correct as the gear set produces a gear reduction when the planetary carrier is the input member, which is a characteristic of planetary gear sets. Therefore, both technicians are correct.

Question 2

Technician A says the check ball in a shaft must be seated in the correct direction. Technician B says some shafts are hollow with internal bushings to support another shaft. Who is correct?

Accepted Answer

Technician A is correct because if the check ball is not seated in the correct direction in the shaft, it can cause issues with pressure regulation and lubrication. Technician B is also correct because some shafts do have hollow centers with bushings to support another shaft, which is a common design in transmissions.

Question 3

Technician A says when an external gear drives another external gear, the output gear will rotate in the opposite direction to the input gear. Technician B says when an external gear drives another external gear, the output gear will rotate in the same direction as the input gear. Who is correct?

Accepted Answer

Technician A is correct. When two external gears mesh, the output gear will always rotate in the opposite direction to the input gear. This is because the teeth on the gears are angled in a way that causes the contact point between them to move in the opposite direction as the input gear. Technician B is incorrect in this case.

Question 4

Technician A says that a compound planetary gear set is comprised of two gear sets that share a common member. Technician B says that some transmissions use a simple planetary gear set added to a compound gear set to gain additional gear ratios. Who is correct?

Accepted Answer

Technician A is correct in stating that a compound planetary gear set consists of two gear sets that share a common member. Technician B is also correct that some transmissions use a simple planetary gear set in combination with a compound gear set to gain additional gear ratios. Therefore, both technicians are correct.

Question 5

Technician A says chassis or white lube is suitable for holding thrust washers and bearings in place during reassembly of the transmission. Technician B says when a planetary gear set with blacken gear shafts should be replaced as an unit. Who is correct?

Accepted Answer

The answer of Technician A says chassis or white lube...

Question 6

Technician A says when an external gear is in mesh with an internal gear, the two gears will rotate in the same direction. Technician B says there will be a torque increase when an external gear drives and is in mesh with an internal gear. Who is correct?

Accepted Answer

Technician A is correct in stating that when an external gear is in mesh with an internal gear, the two gears will rotate in the same direction. This is due to the fact that the teeth on each gear are aligned and interact with one another, causing motion in the same direction.

Technician B, on the other hand, is incorrect. There will not necessarily be a torque increase when an external gear drives and is in mesh with an internal gear, as torque depends on a variety of factors such as gear ratio, number of teeth, and power input. Additionally, the mention of torque increase implies that there is some sort of comparison being made, which is not present in this statement. Therefore, Technician B's statement is incorrect.

Question 7

Technician A says when the planet carrier is the driving member of the gear set and the sun gear is held, overdrive occurs. Technician B says if any two of the planetary gear set members receive torque in the same direction at the same speed, the third member is forced to turn with the other two and direct drive is the result. Who is correct?

Accepted Answer

Technician A is correct. Overdrive occurs when the planet carrier is the driving member and the sun gear is held.

Technician B is also correct. If any two members of the planetary gear set receive torque in the same direction at the same speed, the third member is forced to turn with the other two and direct drive is the result. This is known as the principle of operation of planetary gear sets.

Question 8

Technician A says a faulty output shaft can cause vibrations. Technician B says an unbalanced torque converter can cause vibrations. Who is correct?

Accepted Answer

Both technicians are correct. A faulty output shaft can cause vibrations as it is responsible for transferring torque from the transmission to the wheels. An unbalanced torque converter can also cause vibrations as it can create an unbalanced force in the drivetrain.

Question 9

Technician A says in order to provide additional gear ratios, most transmissions are equipped with more that one planetary gear set. Technician B says that from a single planetary gear set, five forward gear combinations are possible, although some of these combinations are seldom used. Who is correct?

Accepted Answer

Both technicians are correct. In order to provide additional gear ratios, most modern transmissions are equipped with multiple planetary gear sets. From a single planetary gear set, five forward gear combinations are possible, although some of these combinations may not be commonly used.

Question 10

When an external gear is in mesh with an internal gear, both gears will rotate in which direction?

Accepted Answer

When an external gear meshes with an internal gear, both gears rotate in the same direction. This is due to the way the teeth of the gears interact with each other, which is different from the interaction in a pair of external gears, where the gears rotate in opposite directions.

Question 11

Technician A says gear reduction is accomplished by holding the sun gear and applying torque to the ring gear. Technician B says gear reduction can also occur if the ring gear is held and the sun gear is the input gear. Who is correct?

Accepted Answer

Both technicians are correct. Gear reduction can be accomplished by holding the sun gear and applying torque to the ring gear or by holding the ring gear and applying torque to the sun gear.

Question 12

Technician A says only one gear reduction forward gear can be provided by a single planetary gear set. Technician B says only one reverse gear can be provided by a single planetary gear set. Who is correct?

Accepted Answer

Technician B is correct. A single planetary gear set can provide different gear reductions in forward and reverse directions.

Question 13

Technician A says etching is a discoloration or removal of some material caused by corrosion or some other chemical reaction. Technician B says thrust washers should be replaced with new ones if they are pitted or scored. Who is correct?

Accepted Answer

Technician A is correct in defining etching as a discoloration or removal of some material caused by corrosion or some other chemical reaction. Technician B is correct in stating that thrust washers should be replaced with new ones if they are pitted or scored, as this can cause damage to the engine or transmission. Therefore, both technicians are correct.

Question 14

Technician A says the sun gear in a planetary gear set is the central gear. Technician B says planet gears are in constant mesh with the sun and ring gears. Who is correct?

Accepted Answer

Technician A is correct because the sun gear is indeed the central gear in a planetary gear set. Technician B is also correct because planet gears are in constant mesh with the sun and ring gears. Therefore, both technicians are correct.

Question 15

​Technician A says sprag and roller clutches should be inspected in the same way as bearings. Technician B says to check their operation by attempting to rotate them in both directions. If working properly, they will allow rotation in both directions. Who is correct?

Accepted Answer

Sprag and roller clutches should be inspected like bearings, but they should only allow rotation in one direction, not both.

Question 16

In the Simpson gear train with the planet carrier as the output, the carrier will always:

Accepted Answer

In a Simpson gear train, the planet carrier's rotation direction is determined by the input gear's rotation. Since the planet gears are mounted on the carrier and mesh with both the sun and ring gears, the carrier's rotation direction will follow the input gear's direction, assuming a direct drive scenario without additional mechanisms to reverse the direction.

Question 17

Technician A says when the planet carrier is the input, the output gear member always moves in the opposite direction to the planet carrier. Technician B says when the planet carrier is the output, the planet carrier always follows the direction of the input member. Who is correct?

Accepted Answer

The answer of Technician A says when the planet carrier...

Question 18

Technician A says when an internal gear drives and is in mesh with an external gear, there will be a speed increase. Technician B says when an external gear drives another external gear, the output gear will rotate in the opposite direction to the input gear. Who is correct?

Accepted Answer

The answer of Technician A says when an internal gear...

Question 19

Technician A says the input shaft of the transmission connects the output shaft of the TC to the driving members inside the transmission. Technician B says the output shaft connects the driven member of the gear sets to the final drive gear set. Who is correct?

Accepted Answer

Technician A is correct as the input shaft does connect the output shaft of the TC to the driving members inside the transmission. Technician B is also correct as the output shaft does connect the driven member of the gear sets to the final drive gear set. Therefore, both technicians A and B are correct.

Question 20

When the planetary carrier is held, the gear set produces which of the following conditions?

Accepted Answer

The answer of When the planetary carrier is held, the...

Quiz 8: Gears and Shafts