1. Raise and suitably support the vehicle, if required. Refer to Lifting and Jacking the Vehicle in General Information.
2. If equipped with the 6.6L or 7.2L engine, with regular production options (RPOs) MK0/MPU/MM7/MSC and MWW, disconnect the vehicle speed sensor (VSS) electrical connector.

•	If equipped with RPO JE3 (2)

•	If equipped with RPO JE4 (1)




3. If equipped with the 8.1L engine, with RPOs MSC/MPU disconnect the VSS electrical connector.

•	If equipped with RPO JE3 (2)

•	If equipped with RPO JE4 (1)

4. Remove the VSS.

Important: A NEW VSS has pre-applied thread sealant on the threads.

Notice: Refer to Fastener Notice in the Preface section.




1. If installing the old VSS, apply thread sealant GM P/N 1234600, (Canadian  P/N 10953480) or equivalent to the threads.
2. Install the VSS.

Tighten
Tighten the VSS to 48 N·m (35 lb ft).

3. If equipped with the 8.1L engine, with RPOs MSC/MPU connect the VSS electrical connector.



4. If equipped with the 6.6L or 7.2L engine, with RPOs MK0/MPU/MM7/MSC and MWW, disconnect the VSS electrical connector.

•	If equipped with RPO JE3 (2)

•	If equipped with RPO JE4 (1)

5. Lower the vehicle, if required.