Question 1

Two technicians are discussing transmission service on an Allison transmission. Tech A states that the internal filter should be changed every fluid service. Tech B states that the external filter is only changed during the first service. Who is correct?

Accepted Answer

The internal filter of an Allison transmission is typically not changed at every fluid service, and the external filter should be changed more than just during the first service.

Question 2

A vehicle with an Allison transmission comes in to the shop with poor acceleration and no reverse. You test drive the vehicle and determine that there is no 1st or reverse gear. Tech A states that the problem could be a bad C3 clutch. Tech B states that the problem could be a bad C5 clutch.
Who is correct?

Accepted Answer

The answer of A vehicle with an Allison transmission comes...

Question 3

You are testing the solenoids on an Allison transmission and find the resistance of the trim solenoids to be 12.3 ohms. Tech A states that the solenoids need to be replaced. Tech B states that the resistance should be higher than 12.3 ohms. Who is correct?

Accepted Answer

The resistance of the trim solenoids should be between 10-15 ohms.

Question 4

An Allison transmission comes in to the shop with ratio error codes for all gears. Tech A states that the transmission output shaft speed sensor could be faulty. Tech B states that the output shaft speed sensor can be checked with a DC voltmeter. Who is correct?

Accepted Answer

Tech A is correct because a faulty output shaft speed sensor can cause ratio error codes for all gears.

Question 5

A vehicle with an Allison transmission comes in with slipping 4th, 5th and 6th gears. Tech A states that the problem could be a burned C1 clutch. Tech B states that the problem could be a bad shift solenoid. Who is correct?

Accepted Answer

The answer of A vehicle with an Allison transmission comes...

Question 6

What does the transmission use to attain the different gear ratios?

Accepted Answer

The transmission uses multiple disc clutches to engage and disengage different gear sets, allowing it to attain various gear ratios.

Question 7

Choose the correct statement with respect to solenoids.

Accepted Answer

The shift solenoids do not directly act on the transmission clutches. Rather they move valves in the valve body.

Question 8

The resistance value of the torque converter clutch solenoid is:

Accepted Answer

The typical resistance value for a torque converter clutch solenoid is usually within the range of 8-15 ohms.

Question 9

All of the following statements with respect to the speed sensors are true except:

Accepted Answer

The answer of All of the following statements with respect...

Question 10

The internal filter needs to be changed:

Accepted Answer

The answer of The internal filter needs to be changed:
...

Question 11

Tech A states that Allison transmissions use two trim solenoids to control pressure. Tech B states that the transmission uses two pressure control solenoids. Who is correct?

Accepted Answer

The answer of Tech A states that Allison transmissions use...

Question 12

You test the line pressure on an Allison transmission and find that the pressure is only 90 psi (621 kPa) in all gears. Tech A states that solenoid A could be in fail safe. Tech B states that solenoid B may not be energized. Who is correct?

Accepted Answer

The answer of You test the line pressure on an...

Question 13

Tech A states that the shift solenoids in an Allison transmission are pulse width modulated to control the shift feel. Tech B states that the trim solenoids are proportional current solenoids. Who is correct?

Accepted Answer

The answer of Tech A states that the shift solenoids...

Question 14

Tech A states that the two trim solenoids on an Allison transmission are both normally closed. Tech B states that one trim solenoid is normally open, while the other is normally closed. Who is correct?

Accepted Answer

One trim solenoid is normally open, while the other is normally closed.

Question 15

Which of the following statements is NOT true regarding the Allison transmissions?

Accepted Answer

Allison transmissions typically use similar rebuild kits across different models, making option C incorrect.

Question 16

Which of the following Allison transmission models does NOT come equipped with a parking pawl?

Accepted Answer

The answer of Which of the following Allison transmission models...

Question 17

Technician A says that the Allison 1000 transmission contains four shift solenoids. Technician B says that the Allison 1000 contains two trim solenoids. Who is correct?

Accepted Answer

The answer of Technician A says that the Allison 1000...

Question 18

Technician A says that the diesel engine equipped Allison 1000 transmission uses an engine speed sensor. Technician B says the engine speed sensor is not used on gasoline powered engines. Who is correct?

Accepted Answer

Both technicians are correct. Diesel engines with the Allison 1000 transmission use an engine speed sensor, and gasoline-powered engines typically do not use an engine speed sensor in the same way.

Question 19

The Alison 1000 series transmissions has two filters. Technician A says that the outside filter should be replaced at each service. Technician B says that the internal transmission filter only needs to be replaced at the first service. Who is correct?

Accepted Answer

The answer of The Alison 1000 series transmissions has two...

Question 20

Technician A says that during a shift, one of the two clutches from the previous gear will remain engaged. Technician B says that when shifting, one of the new gear clutches will engage. Who is correct?

Accepted Answer

In dual-clutch transmissions, one clutch remains engaged from the previous gear while the other clutch engages the new gear, allowing for seamless shifting.

Quiz 28: Allison 1000 and 2000 Series Transmissions