Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: 555 on November 07, 2011, 12:30:33 PM

Title: 98 GC Grinding/knock noise from rear end?
Post by: 555 on November 07, 2011, 12:30:33 PM
Hi, my GC has started to occasionally make a grinding/knocking noise when pulling away from junctions, seems to be coming from the rear diff.
It's only there for example after a trip down the motorway and even then not always but probably getting more frequent.
It's not the same noise as when the clutch plates wore and made noises cornering, this is just when pulling away.
Any ideas? The diff oil was changed about 8k miles ago is it worth a try changing it again?

Thanks.
Title: Re: 98 GC Grinding/knock noise from rear end?
Post by: eastryjeep on November 07, 2011, 01:02:43 PM
If you drain the diff and check the oil for shiny bits at least you will know for sure that's where the grinding is coming from.

Then based on your findings you can either continue the search, or strip the diff down to have a better look-see to decide on your next step, accept-as-is, repair or replace, (select as many as your pocket allows).

If you are exceptionally lucky you may just find it's all down to a broken or siezed rear universal joint!

Lets hope it's a cheap fix.
Title: Re: 98 GC Grinding/knock noise from rear end?
Post by: greggmo on November 07, 2011, 05:15:50 PM
sounds like the clutch packs in the diff. it will need a re build i would think.
Title: Re: 98 GC Grinding/knock noise from rear end?
Post by: Hillbilly on November 07, 2011, 06:26:30 PM
Hi, my GC has started to occasionally make a grinding/knocking noise when pulling away from junctions, seems to be coming from the rear diff.
It's only there for example after a trip down the motorway and even then not always but probably getting more frequent.
It's not the same noise as when the clutch plates wore and made noises cornering, this is just when pulling away.
Any ideas? The diff oil was changed about 8k miles ago is it worth a try changing it again?

Thanks.
Sorry to say that sounds like some of the symptoms I had. LSD completely knackered.
Title: Re: 98 GC Grinding/knock noise from rear end?
Post by: Mike Pavelin on November 07, 2011, 08:44:46 PM
Drain the oil, refill with synthetic 75/140 and a shot of Mopar diff additive.