Service 4-wheel Drive

I just purchased a 2000 Tahoe (2000.5 new body style) with 45000 miles, 5.3L engine. I noticed the "service 4-wheel light" came on last week, but went off after I shut the truck off. Well this week it comes on all the time, usually after driving for about three miles. Is this a regular problem? I really like this truck and hope this is something minor.

It's usually the 4x4 switch or the encoder motor,try replacing the switch yourself(gravy)to save alittle money if this does not fix it take it to a gm service center to check out the encoder motor

I bought a 2000 Z71 about 2 months ago and noticed the same problem. Sometimes the 2WD light would be on, sometimes it wouldn't. I told the dealer about it and they ended up replacing the control module on the dash. I don't know how much this cost but it fixed the problem.

Definitely the switch on the dash...I have a 2000 silverado and had same problem. Found solution here and went to dealer, got new switch for like 60 bucks, followed inst. in service manual to remove face of dash and new switch just plugs right in..no wiring to mess with or anything..problem was resolved after that

Just take the switch out of the dash...open it up and resolder the little solder joints that are cracked. I would resolder all of them just to be safe.

I am having the same problem on an 03 avalanche. Can this light be scanned similiar to a check engine light? if so what are the possible faults?

I just purchased a 2000 Tahoe (2000.5 new body style) with 45000 miles, 5.3L engine. I noticed the "service 4-wheel light" came on last week, but went off after I shut the truck off. Well this week it comes on all the time, usually after driving for about three miles. Is this a regular problem? I really like this truck and hope this is something minor.
Of course the light will go after after you turn the truck off.:lol:

Of course the light will go after after you turn the truck off.:lol:

Good one!!! ROFL :rofl:

Also check the flude level in your front differential. My 99 was a little low causing the light to come on.