What does the service 4 wheel drive message mean on a 2004 Chevrolet Silverado?

Answer 1

A common reason the service 4 wheel drive light goes on in the silverados is a malfunction of the dash mounted transfer case control switch. There is actually a TSB on the switch assembly. This is also the easiest thing to fix. You can buy a new assembly online for around 50 dollars and it should fix the problem. But to be sure, if you are able to aquire one, the next time the light come on, plug a diagnostic computer into the port under the dash and a trouble code should come up which when googled will tell you exactly what is wrong.

Answer 2

no