Ok so here is my issue, My 05 f150 4x4 had a rattle in the front drive shaft so I took it to the shop for new u-joints. Shop determined the ears on the front drive shaft were damaged so replaced the drive shaft with a used one, installed new u-joints and called it good. Got out on the road and it sounded like there was a zip tie on the driveshaft so I took it back, their response was new CV's, still had the issue, took it back. Next fix was new front bearings, still had the issue, next fix was front diff service, still had issue. Removed the front drive shaft and sent it for balancing, still have the issue. The entire time I have been driving without the drive shaft there hasnt been any noise, as soon as the shaft is installed the noise is back. Anyone out there have a sugestion on a fix. I have also had the fluid in the transfer case checked and it is good, has a little slack but not major.

 

with it in 2wd, none of that stuff should be turning anyways. I think you''re dealing
with an incompetent shop. either the IWE ends are not disengaging and there is
something wrong with the differential (did they disassemble? take the cover off? or
service it by just changing the fluid by sucking it out?) because that is the only time
that stuff turns. or the transfer case is locked into 4x4 for some reason and causing
these parts to turn.