have an 06 supercrew fx4.
so issue is from dead stop when i accelerate, i get a let go feeling followed by a squeak times 3. then after three let gos and three squeaks it seems fine. got my brakes all checked and fully replaced everything lubed etc and everything works perfect no seized calipers etc. so could it be my rear diff? checked the oil in there but it seems fine. the driveshaft is a bit out from the t-case but my truck is lifted and i heard thats normal. anyone have an ideas as to what the hell it is? thanx in advance! he threw some friction modifier in the rear diff and thinks that might solve the issue but it seems to have gotten no better.

 

i was told that you have to drain the diff, before you add the friction modifier or else it wont work properly.. then again this is just what i was told per reading other forums

 

Why did you repost?