So I just picked up a 97 jimmy sle, its a really nice truck, 157k, owned by an older guy, a tiny rust spot on the rear drivers side door, $1000. But here's what I noticed, hit the 4x4 button and it tries to click into 4 wheel but then clicks back to 2 wheel, I put it in neutral and tried 4Lo and same thing, drove it to where I parked it until it gets put on the road Monday and tried again, nothing for 4hi but went into 4lo without a problem. Is this an issue with the switch maybe? I had a friend with me that said maybe that or there's an accuator that might be frozen up? This truck has been sitting since summer and the guy said someone else test drove it a few days ago and it went into 4 wheel drive. What do you guys think?

 

actuator should be under the battery tray, they're pricey best bet is a junkyard.