At 33.5k miles, the truck would randomly enter various 4WD modes when started (including 4 Low) or the 4WD system would not engage at all. The dealership replaced the dash switch the first visit, which seemed to help for about a month, then "Service 4WD" message reappeared. The next visit, the encoder motor was replaced and the problem has not reappeared yet (only 35k miles so far...).
This was the first time the service 4 wheel drive light came on. I was told by a person that worked there and also had a Tahoe that they had had problems with this but they hadn't recalled them. I wasn't sure at the time if it would be an ongoing problem or not.
A D V E R T I S E M E N T S
At 33.5k miles, the truck would randomly enter various 4WD modes when started (including 4 Low) or the 4WD system would not engage at all. The dealership replaced the dash switch the first visit, which seemed to help for about a month, then "Service 4WD" message reappeared. The next visit, the encoder motor was replaced and the problem has not reappeared yet (only 35k miles so far...).
- tom_oh, Hamilton, OH, US