Hello. I am very new at this forum, so sorry about my mistakes, I am not very good at writing in english. Week ago I bought 2001XJR supercharged.. With 106k miles on odo. There is one problem now. The diff started be very noisy. When I put throtle, the noise is not so loud, but going without throtle, it is very loud. I am searching for diferent diff, so do I need to buy only XJR diff, or to buy from simple XJ8. Thats my question for today... Thank you.

 

XJ8/XJR differentials are the same as long as it
is a X308 model.

Are you sure it is filled to the correct level?

 

The only diff from the model range you cannot use is the 3.2L model.

It sounds like a bearing issue, input or output bearings, it may even be the propshaft bearing but this is unlikely.

If you buy a replacement, change the fluid and breather pipe before fitting and replace the shims on the driveshafts with your car's shims.

 

The fluid was changed. I bought "RVS" fluid for gearbox/differential,its like a " doctor" . It was writen, that I have to go 100-150km until 3000rpm, but nothing have changed. The sound is like a bearing. When I put full throtle I can't hear it so much, but when is no throtle or 1/4 , then sound is very loud...and it is diferent all the time. Its like wave,everytime is diferet sound, how to say, its dificult. There is used diff for sale for 100euros, I think its not big price. But its very strange, that all this problem came 3 days ago. I have this car for a week, but this sound just came out, without any small noises. Otherway, the rest of the car is good, all interior, body is really in good condition. If somebody is interested, I will post pictures of my car later.

Thank you very much guys, for your attention.

Regards,

Evaldas