I have a 91 GMC K1500 4WD and while plowing this past weekend the 4WD stopped working. The truck was turning left when there was a clunk and the front wheels stopped working. We checked the front axles and they do not appear to be getting any power. The lever engages but the light does not go on. You can hear some grinding in the transfer case if you leave it in gear, so something appears to be trying to engage. The 4WD is engaged with a lever, not a push button. The 4wd indicator light was working before the 4wd stopped working as well. I have read that the actuator can go bad, but I’m not too familiar with the 4wd on this truck. There looks like there are no vacuum lines going to the transfer case, however, there is an electrical connection. Has anyone had similar problems and what was the problem. Thanks.
Mike
sounds like you trashed the transfer case i did this to my 92 the cause was i had different sets of tires on it the front were p255 65 r15 the rear were p255 70 r15 i didnt think it would matter but i learnd the hard way 900 in new parts later…for a new transfer case