A few questions - rear end issues.

Hi folks,

Great forum -- apreciate the resource.

These question are in regard to a 2001 4wd.

Recently I replaced both u joints on the rear driveshaft.

Question 1 - what is the proper method for centering the rear u joint to the diff? It seemed like I have about 1/2" of range to where I bolt it in with the straps.

I've also been having some rear end (I *think*) vibration issues for the last year or two. It's the worst around 60-90km/hr. Not horribly shaky, but its getting to the point where I am starting to get concerned. It makes a small whirring/thumping sound, quite high speed. I'm thinking it's the rear diff but if anyone here has any suggestions or ideas please tell me.
(This vibration seems to be significantly worse since I replaced my universal joints -- I believe its possibly related to them not being properly centered on the diff)

Thanks folks!
Really appreciate it.

I am having the same thing with my 200 blazer I wonder if anyone has an ideas or can explain what to loook for or how to fix it thanks

Wow, I'm glad you found this thread.  I must have missed it back when it was originally posted.

To the OP, as far as centering the u-joint into the yoke on the rear differential...  Things should go together quite snug on the rear yoke.  Atleast they did on my 2000 Bravada when I replaced the rear u-joint.  Are you sure that you have/had the correct parts? 

To the poster above, have you had any work done recently?  If so, what did you have done?  If not, what troubleshooting steps have you performed to attempt to narrow down the problem.  For u-joint diagnosis, you should be able to grab the driveshaft and attempt to move it around.  If you feel/see any play in either end, the u-joint on that end should be replaced.

 put in new u joints and checked brakes and calipers all good thanks. I am thinking it is in the rear end but not sure what to look for