Lsd Clunking

[Godzilla32]

Hey guys,

Anyone had their factory LSD in an R32 GTR start clunking on and off throttle? Mine started to after a few hard launches and has progressivly gotten worse. At first i wasnt sure what the noise was but after checking out everything the only thing i found was that when its raised up i can spin one rear wheel while holding the other. They arent locked together anymore as they should be. There seems to be alot of backlash and i think thats the noise im hearing but it seems to be linked to this open centering of the LSD. Might not be but it used to be locked tight together..

Ive heard of 'tabs' breaking from the LSD? I have tried changing oil and made sure it was an LSD oil im using.

Anyone got any info for me?

Cheers,

Deren

[DVS JEZ]

It wont be the lsd. It will be the crown wheel and pinion inside the diff. Mine does it now too.

[bigmikespec]

Mine does it too; sounds terrible... does it mean they are worn out? Or they just need to be rebuilt with proper meshing between pinion and crown?

[bigmikespec]

Well... because it was annoying me I spoke to a diff. place and he mentioned that a f**ked bearing may increase the backlash of the crown and pinion. In my case I get a whirring noise too at low speed as well as the "clunking". Looks like diff. out this weekend

[Godzilla32]

Hmm so its a coincidence that the lsd is worn out too? It makes sense what your saying as it sounds like too much backlash. As i mentioned it just seemed to be related to the lsd as i noticed it was worn out now too. Im just completing an lsd rebuild at work on a 32 gtr with the same symptoms. However the backlash wasnt excessive on this car.. When i pulled down the lsd centre the cover didnt have a great deal of preload on it. Since ive rebuilt it, the lsd case has alot more preload on it. Another thing to note was that there are only 6 individual plates per side. 2 spring plates, friction plate, 2 friction discs, another friction plate then the pressure ring. In the manual and FAST it shows there should be an extra shim per side. When i tried to fit these extra shims on the lsd at work it was over loaded and id guess it would have locked it too tight like a locker. I'll post up how it behaves once the one at work it all back together and in the car.

Deren

[Rolls]

It could be multiple things, worn out clutch plates causing it to open wheel and excessive backlash causing the clunking, could also be a worn uni joint/bearing causing it clunk as well though.

[Chris32R]

Mine only started clunking last week. When reversing and you are on the friction point the drivetrain starts shuddering. In 1st it does it slightly but all other gears are fine. The gearbox was removed and refitted to fix a rear main seal at around the same time it started happening.

Any ideas what this could be and how to fix?

Sorry for the slight thread jack but it could be related.

Thanks.

[DVS JEZ]

they didnt atighten the clutch pressure plate correctly causing clutch shudder, is it a new clutch or just remove and refit yours?

[Chris32R]

Hmmm the clutch is aftermarket but was just a remove and refit when they did the rear main seal.

If I drive it like that will it do any damage to anything?

Would that mean they would be responsible to fix it at no cost to myself?

Thanks for the help.

[Rolls]

Mine only started clunking last week. When reversing and you are on the friction point the drivetrain starts shuddering. In 1st it does it slightly but all other gears are fine. The gearbox was removed and refitted to fix a rear main seal at around the same time it started happening.

Any ideas what this could be and how to fix?

Sorry for the slight thread jack but it could be related.

Thanks.

Sounds like a typical heavy duty clutch, what kind is it?

[Chris32R]

Xtreme single plate ceramic clutch. It used to clunk slightly on occasions like a normal heavy duty clutch would but you could drive around it. After it came back from the repair it did it pretty badly in reverse and slightly in first when taking off. It never used to do this before then.

[Rolls]

Ceramic, is that like a brass button?

[Godzilla32]

Shuddering heavy duty clutches is very normal but perhaps they got some oil on the flywheel or pressure plate and didn't clean it. Always a good idea to clean surfaces with shellite or similar. So nothing to do with clunking diff.

I've decided it's excessive backlash in mine but can't work out why it's getting worse with no other symptoms like gear noise etc. Also can be a good idea to rough up flywheel and pressure plate to help it bite with emery tape..

Edited October 21, 2010 by Godzilla32

[blue_vl_t]

Thought id post here insted of starting a new thread.......

R32 GTR, i'm having similar problems with lash in the rear diff, I'm able to turn the tailshaft about 15-20mm round each way before the diff takes up, if you get my drift.

so there is exessive lash in the crownwheel and pinion, the drive shafts dont move while doing this so the movement is in the centre itself.

I cant imagine the gears wearing that far and would asume the pinion bearing is collapsed??

Is this what other people have found when rebuilding their diff's with these symptoms?

As a side note the diff seems to twin whell fine, just clunky at low speed.

if this seems fesible then are bearings easily avaliable or am i looking at genuine nissan parts for all?

any help appreciated

[bigmikespec]

Mine is clunky at low speed too it is a Vspec diff. It could be a mixture of bearing and worn out CWP's. I have a spare mech. diff. and I also bought brand new set of CWP's too. A diff. place can usually match the OEM parts with an aftermarket one.