Evertime i hit the gas or let off after accelerating there is a fairly loud clunk coming from somewhere in the rear of my truck. I checked the u-joints and there fine. Could it be the ring&pinion or the transmission. I'm hoping it's the tranny becasue it already makes clicking noises evertime it's moving that are easly heard from in the cab. I'm thinking of getting a new tranny, but would a rebuild solve this problem? It's a E4OD.

 

Double check your tranny mounts and engine mounts while you are at it.

I think the typical reply you will get from this is grease up the spline on your slip yoke. Worked for me. Good luck.

 

What truck are you working on?

Check the yoke nuts on the axle pinion and the t-case (4WD only) - they sometimes get loose, allowing the shafts to wobble in the bearings.

 

I was havin the same problem with my 2001 screw after only 35,900 miles. My dealer couldnt seem to find the problem( convieniently). He had the truck 2 differnt times. I took it to my personal mechanic and he said that it was the differntial pin that was worn and cracked, which made it loose so it clunked when I excelerated. Now Ford can pay my mechanic!