I have an 01 XJ 4.0 with D35 trac-loc rar axle, which is making a strange squarking noise during sharp turns. I have had the cover off the diff for a look-see, but cannot find anything obviously amiss, oil was a little goopy, but no metal bits or shavings, no unusual wear on the diff gears. it only does it during a sharp turn, so maybe an issue with the LSD? Any opinions/advice will be appreciated, cheers.

 

I don't know anything about the D35, but I'm assuming it would require a LS additive. Did you add any with the new gear oil?

 

The new oil was supposed to be lsd oil, but do you think i'd need an additive anyways? The noise isn't as bad as it was and it no longer shudders when i turn, and it'll only start to make any noises once it's warmed up abit, after maybe 15 mins driving. Also, if i run in full time 4wd on the road, no noises. I can only assume this is because some of the load is taken off the rear diff when in 4by?

 

Unless you can be sure the oil you put in has the proper friction modifier, put some in there. Then do some figure 8 turns to get it worked in. That should help quiet it down. If it doesn't, you may need new clutches.

 

Based on the fact that you've probably been driving on it for a while I would almost think that the clutches are getting worn down to a point where they're sticking or something along those lines. However you could just try adding some limited slip additive or friction modifier to see if that will help unlock it as a previous poster said. Worst comes to worst the friction modifier sets you back 8 bucks at your local auto store

 

Just add a little at a time until the shudder goes away.

 

Ok, Cheers to all for the replies. I'll give it a try and see how it goes