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: 28390  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 two 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. In order to determine the correct low and reverse band servo piston pin length, 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).
  7. 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 .
  8. 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.