unfortunatelyI changed those about a month ago

 

No it does not do it At a stop. But as soon as I start moving it disengages, with a loud clunk you can definitely feel, almost like u-joints but I already changed the joints on the front axle.

 

It seems like low vacuum pressure. Have you checked the vacuum on the lines that go to the CAD unit with a gauge? I believe it is supposed to be about 20psi.

 

Good point, I did not mention the light does not go off. It stays on the entire time. The floor shifter stays where it supposed to be, ( in 4H or 4L) But it almost sounds like a large chain binding on a large sprocket or gear and then catches, almost like your bike when you were a kid. The chain would be coming up around the large sprocket (about to pop off) but then catch and continue to spin around. I hope you can relate to that poor analogy, but it makes total sense to me. I hope it helps you.

 

Well, appreciate you chiming in but with all due respect this is definitely not normal. The whole truck shakes when it happens, it happens about every 3 to 4 seconds and is not drivable at this stage, at least not in 4 wheel drive

 

How fast are you going when it does this, also where does it shake in the steering wheel or does the front end shake. does it only shake under heavy exceleration etc etc.

I personally would say if it is at high speed the tires could possibly be out of balance, also if you have ever had a flat and used fix a flat it will cause your tires to go out of balance. Also it would be because of bad U joint's, have you checked your shock towers ? make sure they'er all tight, There is 3 bolts on both sides, 2 on the inside of the wheel well and one on the frame inside the engine bay if either one of those shock towers are loose it will cause shifting or vibration under strain. When you are in 4x4 mode it causes alot more stress on the front suspenion and will cause thing's to wobble and wiggle when normally they wouldnt.

Thats just my opinion on where you could look IF any of them seem to fit your case.

 

Do you feel it in the floorboard, or more towards the front of the truck? The reason I ask, is I had a Wrangler (231J t/c, ours is a 231HD) and the PO put regular gear lube in it. After getting so frustrated, I thought to check the fluid. It was light brown (like gear lube), so I drained it, sprayed brake cleaner in there, and filled it back up with ATF. Worked fine until I sold it. Might be your problem? Or low fluid in the t/c?? Its pretty easy to check. I think it was causing binding up in the t/c chain... Just a thought.

 

I posted a link for you,that will give you all the info you need to diagnose the problem. Have you looked at it?