GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • J 21370-10 Band Apply Pin Gage
    • J 38737 Band Apply Pin Checking Tool

For equivalent regional tools, refer to Special Tools.


    Object Number: 31240  Size: SH
  1. Install the J 21370-10 pin gage into the low and reverse band servo pin bore.
  2. Position the J 38737 pin checking tool over the low and reverse band servo bore with the hex hub facing the parking pawl linkage.
  3. Caution: Refer to Fastener Caution in the Preface section.

  4. Fasten the J 38737 pin checking tool to the case with 2 low and reverse band servo cover bolts (61). Tighten the bolts to 24 N·m (18 lb ft).
  5. Verify that the J 21370-10 pin gage moves freely in the J 38737 pin checking tool and in the low and reverse band servo pin bore.
  6. Note: The hex hub of the J 38737 pin checking tool must be tightened in order to determine the correct low and reverse band servo piston pin length.

  7. Tighten the hex hub of the J 38737 pin checking tool . Tighten the hex hub of the J 38737 pin checking tool to 34 N·m (25 lb ft).
  8. Observe the lands on the J 21370-10 pin gage in order to determine which land is even with the top edge of the J 38737 pin checking tool . Note the letter (A, B or C) stamped on the J 21370-10 pin gage .
  9. Refer to the Low and Reverse Band Servo Piston Pin Specification table, in Transmission General Specifications , in order to determine the correct pin length to use.
  10. Remove the tools.