Have noticed that truck is disengaging going down the road..... a big bang then no 4wd. At hwy speeds!! Have not been able to see if light in dash is going out at same time because of harsh jolt/ noise it gives when this is happening. I would assume that it is the cad,but I have cad apart and it seems to hold vac. when sucking on it. What could it be? truck has 100,000 on it. All vac lines intact and hooked up. switch in case maybe? thanks, Nate

 

Have noticed that truck is disengaging going down the road..... a big bang then no 4wd. At hwy speeds

Driving down solid road in 4WD. I'm sure will bind case and pop out if can. The other option is chain jumps.
Read the owners manual on 4WD operation.

 

driving down h-way has nothing to do with it. the shift fork to engage 4wd has teflon/plastic tabs on tips of fork, good chance they are worn out or missing. the shift fork could also be worn/bent. this will cause partial engagement thus dis-engaging. either way the case needs to be gone through .

 

Guys, I've owned a few 4wd's in my day....... and driving down a snow covered or not road does not cause bind or problems with case or front end/cad. I have yet to see 1 jump out of 4wd in this situation until now. A 3 point turn on dry pavement, yes will cause front end to bind in 4wd. The fork is not bent and pads are intact,I have cad out and inspected. Looking for a Tech. someone that has had/ or heard of same situation thanks though, Nate

 

mentioned fork is in the transfer case. verify the shift linkage is not worn though. i have seen a few nv241,231's with like concern.

 

Thanks for reply, thought you were talking 'bout cad. Hate to pull and split case bout it looks like I might have to. Nate