Rear differential inspection

ExodoPlex

New member
May 20, 2020
2
0
SouthWest United States
On my 2003 Disco 2, I've got some knocking coming from the back end and after checking all the watts linkage and sway bar links for movement, as well as completely replacing the rear driveshaft with a brand new one, I've decided it must be coming from inside the diff. Sounds like a broken U-joint.

My question is this, what am I looking for besides the obvious? Is there a trick to determining if the diff needs to be rebuilt/replaced? Or is it pretty straight forward, "see broken, replace broken"?
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
What does a broken u joint sound like? I'm guessing one really loud snap and then the driveshaft bouncing between the road and the bottom of the truck?
 

Jimmy

Well-known member
Apr 10, 2006
740
64
Aurora, CO
I'm guessing the noise is a clunk... at least that's what failing u-joints usually sound like before they completely fail.

I'm envisioning the center pin is clunking around in oval'd out holes in the carrier.
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
I'm guessing the noise is a clunk... at least that's what failing u-joints usually sound like before they completely fail.

I'm envisioning the center pin is clunking around in oval'd out holes in the carrier.
He didn't say loose. He said broken. Loose clunks, what is broken?