GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2002 🢒 Firebird 🢒 Engine 🢒 Engine Electrical 🢒 Transmission Locked in One Gear

Diagnostic Aids

If the transmission is locked, engaging the clutch will stall the engine. If the shift control components and the clutch system operations are working properly, the condition is caused by internal damage, such as a dented or damaged shift fork. The transmission must be removed from the vehicle for repairs. You should perform a static shift test and a dynamic shift test before removing the transmission from the vehicle.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step inspects for a faulty actuator cylinder.

    2.

  2. This step inspects for worn or damaged internal parts.

Step

Action

Yes

No

DEFINITION: The transmission cannot be shifted out of a gear.

1

Did you review the manual transmission symptom and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Manual Transmission

2

Test the transmission fluid level. Refer to Transmission Fluid Level Inspection .

Is the transmission fluid level correct?

Go to Step 3

Go to Step 4

3

Add transmission fluid if necessary.

Did you find and repair the condition?

System OK

Go to Step 4

4

Inspect for the correct type transmission fluid.

Is the correct type transmission fluid being used?

Go to Step 6

Go to Step 5

5

Drain and refill the transmission with the correct type fluid. Refer to Transmission Fluid Replacement .

Did you find and repair the condition?

System OK

Go to Step 6

6

Inspect the clutch actuator cylinder operation.

Is the clutch actuator operating properly?

Go to Step 8

Go to Step 7

7

Replace the clutch actuator cylinder. Refer to Clutch Actuator Cylinder Replacement .

Did you find and repair the condition?

System OK

Go to Step 8

8

  1. Remove the transmission. Refer to Transmission Replacement .
  2. Disassemble and inspect the transmission for a dented or damaged shift fork.

Is there a dented or damaged shift fork?

Go to Step 9

Go to Step 10

9
  1. Replace the worn or damaged components as necessary. Refer to Transmission Disassemble in the Transmission Unit Repair Manual.
  2. Install the transmission. Refer to Transmission Replacement .

Did you find and repair the condition?

System OK

Go to Step 10

10

Disassemble and inspect the transmission for a incorrectly assembled or broken shift mechanism.

Is there a incorrectly assembled or broken shift mechanism?

Go to Step 11

Go to Step 12

11
  1. Replace worn or damaged components as necessary. Refer to Transfer Case Unit Repair Manual.
  2. Install the transmission. Refer to Transmission Replacement .

Did you find and repair the condition?

System OK

Go to Step 12

12

Disassemble and inspect the transmission for a worn or damaged geartrain component.

Are there any worn or damaged geartrain components?

Go to Step 13

--

13
  1. Replace worn or damaged geartrain components as necessary. Refer to Transfer Case Unit Repair Manual.
  2. Install the transmission. Refer to Transmission Replacement .

Did you find and repair the condition?

Go to Step 14

Go to Diagnostic Aids

14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 1