dlindsey19
Newbie
Hey guys I've got an interesting problem with my Suburban. 1998 GMC K2500 Suburban, 454, 4L80E, NP246 auto 4wd transfer case. Ever since I bought the truck and used the 4x4 in the snow here in SE Idaho it's done this. What happens is if you leave the truck in 2wd, then go to 4hi and drive for any sort of distance (more than about half a mile), the service 4wd light comes on and the truck stays in 4hi and will not come out. If you use the 4hi for less than that (like to get out of a driveway or something) and then switch back to 2hi, it works fine. When it doesn't, when you press 2hi or 4Lo or any other button, it does nothing. Only way to get it to switch back is to unplug the switch on the dashboard or shut the truck off and wait five minutes, start it up and then it goes away. I replaced the switch on the dashboard, the transfer case and encoder motor (for other reasons, cracked the housing with a bad u joint), and trying to pull up the codes shows nothing. I don't think it's the actuator because if it was, how would it switch back and forth if you use it for a short period of time? The only codes that seem remotely close to the issue are for the abs front wheel speed sensors. Could those be it? I'm puzzled and lost, any advice is appreciated. Thanks!
