Clutch LSD and warrants

[Dragger_Dan]

Hi all,
Just took the AW11 for its first warrant and ran into a bit of a problem.

The warrant guy said there was noise and vibration coming from the drivetrain. I asked if it was only at low speed/tight turn and he said yes. I explained to him that it had a clutch LSD in it and that type of diff will do that under those circumstances. He said that it would have to be fixed.

I jacked up the car later and checked the driveshafts, no play in them. You can get about an inch of rotation out of each wheel before it locks up (with the other side on the ground).

So, a few questions:
1) Is that normal for a TRD diff to make a bit of noise at low speed/tight turn?
2) The inch of play before it locks is just to do with preload, right?
3) If this sounds normal to you, how do I convince the warrant guy that nothing is wrong?

Thanks.

[Bazda]

Some warrent guys LOL

Yes all TRD clutch pack LSD will make this noise if your not running the TRD gear box oil for it.
This is cos the clutches are trying to slip and grip.
The TRD oil has an additive in it to make it a bit slipprier allowing the clutch packs to slip quietly.. in another words.

[DRFTIN]

haha
i'd tell him to identify the illegal part
is he going to tick the "i dont know whats wrong with this box"?

[Maxwedge]

My FXGT does the same, some of those WOF mechanics are a bit thick and narrow minded when it comes to factory legal modifications, they just cant get their heads around a motorsport plate LSD vs a road LSD like a viscous or torsen type. I have tried various oils but stick to Redline shockproof superlight gear oil ( its fantastic with worn synros) however it does not have the slippery additive. This additive can be purchased separately and topped up to increase th slipperyness.
I have also used Automatic transmission fluid (dextron 3) this stuff works well and takes all the aggressiveness (knocking, clunking and grabbing) out of the plate LSD action, but still locks up good when under power. Auto transmissions have clutch plates inside and require this additive which I believe is in the dextron 3 fluid.

[Maxwedge]

The answer to your questions are yes! The plate LSDs are noisy, my two gearboxes have the same preload desription (however thats not the correct way to measure the preload) and I would search out a motorsport friendly garage and get a WOF from them and stick to the same garage to get a history with them making further modifications easier.

[no_8wire]

Not a safety issue anyway? ...Cant fail you on run bearing etc?

[rollaholic]

where can you get the additive from? toyota? my TRD diff could use a bit of it too

(sounds like it could be the easy answer to OPs problem too)

[Dragger_Dan]

Thanks for the help folks. Anybody recommend a WOF shop on the north shore? It's a bitch when you have a perfectly good working car sitting in your garage because some dinosaur just assumes you're a dodgy modder.

[Akane]

PM'd

[AceSniper]

BNT sells Redline LSD additive....
its even more fun then its a plate lsd and fwd....
the wof guys bitch on the test drive that it wont turn under power

[Flannelman]

my dad falcon requires "friction modifyer" for the diff due to the LSD. without adding it the clutches in the LSD bind creating a locker type diff, excessive noise, (think slow moving chatter rings) and hard on all sorts of things.
perhaps adding this will solve the issues? Check with toyota/TRD for correct additve as BNT sell a friction modifyer.

[johndoe1025]

can i ask....was it a VTNZ wof guy?

[Dell'Orto]

my dad falcon requires "friction modifyer" for the diff due to the LSD. without adding it the clutches in the LSD bind creating a locker type diff, excessive noise, (think slow moving chatter rings) and hard on all sorts of things.
perhaps adding this will solve the issues? Check with toyota/TRD for correct additve as BNT sell a friction modifyer.

Is it a AU/BA V8/XR6T by chance?

[KinLoud]

Yeah Acesniper recommended the Redline LSD friction modifier.
I use it in my Marino when I installed a TRD lsd - about 200ml bottle, follow instructions. Worked mint, stopped the grindy clunky sweet!
Take me for a spin next time we do lunch.

Ken
Auck
021 408 863

[Bazda]

I didnt add the friction modifier to mine.

To me as it makes it more slippery, causing the plates to 'slip' better, wont this cause the LSD to not work as well...if you didnt use the friction modifier..

[Maxwedge]

When I ran auto trans fluid in my C52 it felt significantly smoother in its operation with no usual knocks or clunks, however I could still feel the steering wheel pulling going around normal corners. To further check the LSDs operation I dumped the clutch in first @ 7000rpm with a bit of handbrake in our warehouse and the tyre left a couple of nice even black marks 20 metres long (then ran out of room) so running a slippery additive did not seem to me to affect its overall operation.

[molex]

There's slip and then there's SLIP...

slip under low load circumstances is higher desirable, slip under high load is definitely not. You definitely don't want your FWD diff locking while you turn into a driveway. You do definitely want lock when you drop a big dirty burnout in front of your mates parents place.

It would seem that a friction modifier gives you more of the former but probably not any more of the latter. If the manufacturer specifies it, it's probably not going to reduce the effectiveness of their diff.

[method]

It will always make a noise when turning at low speed

Clutch will engage but there isn't enough torque to keep the clutch pack engaged to keep it from slipping so it will disengage and slip then reengage.. Makes a thudding/chattering noise which is normal.

Had a cusco lsd in my evo and it did it a lot. Always got funny looks when trying to park. Either the LSD is chattering away or the wheels would be chirping on the smooth concrete!