Speed Sensor 1999 GMC Sierra 1500 2wheel drive

1998 GMC 1500

My speedometer quit working and also my cruise control. I have replaced the speed sensor on my transmission and also the cluster. Any suggestions?

On that particular year truck it was common for the cluster to fail. Sometimes disconnecting the battery for a minute would reset them but in most cases replacing them was needed. But this would not have affected the cruise control.

I would be interested to know if there are any Trouble Codes present. Like maybe P0500 – Vehicle Speed Sensor A Circuit, etc? Any codes found would help guide us in the right direction.

Other things you could check would be the wiring harness and connectors. Isolate each end of the wiring harness and check for continuity on each wire.

Keep in mind that your vehicle has a speedometer gear/sensor and a separate Vehicle speed sensor located in the rear axle.


Except Corvette

  1. Raise and support vehicle, then remove righthand muffler.
  2. Disconnect vehicle speed sensor electrical connector.
  3. Remove mounting bolt and vehicle speed sensor from rear axle differential case by lifting up and out of hole.
  4. Reverse procedure to install.


  1. Disconnect speedometer cable or pulse generator electrical connector at transmission.
  2. Remove mounting bolt, retainer and pulse generator, then the speedometer driven gear and O-ring seal.
  3. Reverse procedure to install, using new O-ring.