Service 4WD Message May be Displayed on GMC Sierra 2500

Problem Description and Possible Solution

The 4WD transfer case position sensor or the selector switch may fail causing the service 4WD message to be displayed.

Problem Data
RepairPal Verified
Average mileage: 153,200 (61,000–230,000)
Drive Trains affected: 4WD, Automatic Transmission
6 model years affected: 1999, 2000, 2001, 2002, more2003, 2004
12 people reported this problem
Viewing 1 - 3 of 3 problem details
service 4 wheel drive message and lights switch to 4 low or just blink. must turn off p/u to stop and show 2 wheel.
Service 4wd light comes on.
service 4wd light on