GM Service Manual Online
For 1990-2009 cars only

Slips out of Gear General Diagnostic

Step

Action

Value(s)

Yes

No

DEFINITION: The transaxle slips out of gear

1

Inspect the linkage for improper adjustment or wear.

Is there any of these conditions?

Go to Step 2

Go to Step 3

2

Repair or replace the linkage as needed.

Does the transaxle still slip?

Go to Step 3

System OK

3

Inspect that the transaxle is tight on the engine housing.

Is the transaxle loose?

Go to Step 4

Go to Step 5

4

Tighten the transaxle to the mounts. Refer to Fastener Tightening Specifications

Does the transaxle still slip?

Go to Step 5

System OK

5

Inspect the shift linkage.

Does the shift linkage bind?

Go to Step 6

Go to Step 7

6

Repair or replace the shift linkage as needed.

Does the transaxle still slip?

Go to Step 7

System OK

7

Inspect the cables.

Are they bent or worn?

Go to Step 8

Go to Step 9

8

Repair or replace the cables as needed.

Does the transaxle still slip?

Go to Step 9

System OK

9

Inspect the input gear bearing retainer .

Is the retainer broken or loose?

Go to Step 10

Go to Step 11

10

Repair or replace the retainer.

Does the transaxle still slip?

 

Go to Step 11

System OK

11

Inspect the shift fork.

Is the shift fork worn or bent?

 

Go to Step 12

Go to Step 13

12

Repair or replace the shift fork as needed.

Does the transaxle still slip?

 

Go to Step 13

System OK

13

Inspect the clutch housing and engine .

Is the clutch housing or the engine dirty?

 

Go to Step 14

Go to Step 15

14

Clean the clutch housing and the engine.

Does the transaxle still slip?

 

Go to Step 15

System OK

15

Inspect the shift lever seal.

Is the seal stiff?

 

Go to Step 16

Go to Step 17

16

Repair or replace the seal.

Does the transaxle still slip?

 

Go to Step 17

System OK

17

Disassemble the transaxle. Refer to Transmission Case Disassemble

Slips out of Gear While Accelerating

Step

Action

Value(s)

Yes

No

DEFINITION: The transaxle slips out of gear while accelerating or decelerating

1

Inspect the first gear thrust bearing.

Is the bearing missing or showing too much end play?

Go to Step 2

Go to Step 3

2

Repair or replace the bearing as needed.

Does the transaxle still slip?

Go to Step 3

System OK

3

Inspect the first gear washer.

Is the washer missing or show too much end play?

Go to Step 4

Go to Step 5

4

Repair or replace the washer.

Does the transaxle still slip?

Go to Step 5

System OK

5

Inspect the first gear spline lock on the 1st/2nd synchronizer sleeve or the hub.

Is the spline lock worn or damaged?

Go to Step 6

Go to Step 7

6

Repair or replace the lock.

Does the transaxle still slip?

Go to Step 7

System OK

7

Inspect the 2nd gear spline lock on the 1st/2nd synchronizer sleeve or the hub.

Is the lock worn or damaged?

Go to Step 8

Go to Step 9

8

Repair or replace the lock.

Does the transaxle still slip?

Go to Step 9

System OK

9

Inspect the 3rd gear spline lock on the 3rd/4th synchronizer sleeve or hub.

Is the lock worn or damaged?

Go to Step 10

Go to Step 11

10

Repair or replace the lock.

Does the transaxle still slip?

 

Go to Step 11

System OK

11

Inspect the 4th gear spline lock on the 3rd/4th synchronizer sleeve or hub.

Is the lock worn or damaged?

 

Go to Step 12

Go to Step 13

12

Repair or replace the 4th gear spline lock.

Does the transaxle still slip?

 

Go to Step 13

System OK

13

Inspect the 5th gear spline lock on the 5th synchronizer sleeve.

Is the spline lock damaged or worn?

 

Go to Step 14

Go to Step 15

14

Repair or replace the 5th gear spline lock.

Does the transaxle still slip?

 

Go to Step 15

System OK

15

Inspect the reverse gear spline lock.

Is the lock damaged or worn?

 

Go to Step 16

Go to Step 17

16

Repair or replace the lock.

Does the transaxle still slip?

 

Go to Step 17

System OK

17

Disassemble the transaxle. Refer to Transmission Case Disassemble

   

Slips out of Gear While Coasting

Step

Action

Value(s)

Yes

No

DEFINITION: The transmission slips out of gear while coasting.

1

Inspect the shift rail(s).

Are the rails damaged, worn or missing parts?

Go to Step 2

Go to Step 3

2

Repair or replace the shift rail(s) or any missing parts.

Does the transmission still slip?

Go to Step 3

System OK

3

Disassemble the transaxle. Refer to Transmission Case Disassemble