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Recently replaced all fluids in my R33 GTR with Redline Synthetic and since then a lound crunching sound is coming from the trans when reversing at low speed on lock.

Mechanic and redline assure me this is normal and is called " DIFF CHATTER " or ' clutch chatter '.

Want to know if anyone else has had any experience with this ??

sb..

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axle-tramping... Like... umm.. the rotation of the diff affects how the rear end squats or lifts when you're gunning it.

Mine (stock) will chatter and jump all over the place if I light it up in the wet in 1st gear, but if I switch to 2nd, it's all smooth sailing (sideways).

I get the chattering if I reverse quickly or give it some steering at the same time.

Maybe i'm horribly wrong, and it's just a LSD diff thing... I don't know a lot about what a 1.5-way diff is, but i've heard those specs a few times before. I know what open, LSD, locker, active LSD all are, but this "way" business could be something related?

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yeh if ur clutch doesnt have a spring centre to damper the grip of the two faces when releasing the clutch it will send a shudder or jolt down the drivetrain line which in turn can cause something else to engage too quickly or too roughly which may cause the shudder your experiencing.

The spring centre is purely to help take up some of the initial jolt when the clutch is released. Makes for a smoother drive normally. My car has a sprung centre and its beautiful, the race car has no sprung centre and its really jolty and clunky, makes you think something is wrong with gearbox when u release it.

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Don't mean to hijack your thread mate, but my car does the same sort of thing. I'm under the impression i have a locker diff, it's just very inconsistent on when it wants to make some noise. It gets people looking at my car for the wrong reasons. :D

But what R33 racer has said has me thinking now, as "sometimes" I can feel the shudder actually beneath me from the rear of the car, other times it's just at the back. I have had the oil changed to redline lightweight, but i need to change it again to a heavier oil. Lightweight makes it good for less friction, but i don't need it for racing!

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Guys this link might be of some benefit to you.

I am also a Rex club member.

Please see this link.

Note sti05's posts and STIRA and lastly closed deck who owns Urban Racing Developments

http://www.wrx.com.au/forum/viewtopic.php?...ghlight=redline

Edited by PATR33
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link doesnt work.

The original post sounds like its just the diff noise from the change in oil..other people have mentioned their diffs clunk more with redline oil in it more noticably in reverse and or while some form of steering lock is applied. The oil maybe lighter and have a tendancy to increase any diff noise rather then absorb or dissipate it.

But from what im hearing here about the clutchs...sounds like its a matter of when u engage the clutch without enough revs it clunks and carrys on also...forgot to mention that part previously. Especially if its a ceramic or brass button clutch..and even more so if its a non-sprung centre clutch.

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