Replacement / Repair Of Vspec Diff

[mattymagoo22]

hey paul am in the same boat as you.

As far as i can see the fluid in the resorvoir is similar to atf but its nissan spec and it is yellow when new. The diff oil needs an Lsd oil as it is the same as a mech lsd (clutchs etc) only the pump controls how much preload is applied to the sidegears which gives the Lsd effect. the 2 hydraulic actuators sit on each side of the diff.

I'm tearing my hair out trying to get this system working as it should be a really good unit nice and strong too!

the system behaves like when a mech LSD is worn out by open wheeling, particularly the drivers side wheel. Mine will pull dual wheel burnouts but when you keep going it ends up slipping down the road grrrrrrr!

Im close to just swapping over for a nice tight mech LSD but I'll keep you updated.

Does your a-LSD light come on with the car turned to on but not started? only my slip light comes on and ive never had any of them come on when I've been driving.

cheers.

[paulr33]

when i turn my car to ON (without starting) all my lights come on.

both a-lsd and slip come on. they should to indicate the lights are working and diag is OK. if you dont have a-lsd light come on at post diag then it could be the light is dead, and it may be failing mid flight for you, hence the single spinning ?

if slip doesnt come on when you are loosing traction the computer isnt doing its job and turning the pump on.

i suspect in your case your A-lSD is failing each time at start up and the a-lsd light is dead as well.

do you have the factory ecu or an aftermarket ecu ?

[mattymagoo22]

yeah man all factory ECU

I'm going to check that the globe isn't blown..... one day. I'd really love to get this thing working but I'm seriously thinking about getting an aftermarket unit single spinning is driving me nuts.

I'm a bit worried that the problem may be bigger than I think. The slip light should come on regardless whether the A-LSD does as it comes on at startup... which may mean that the system thinks its working but actually isn't so it could be that the internal clutches are kaput or it could just be that it wants to wreck my brain grrrrrrrrrrrrrrrrrrrrrrrrrrr!!!!!!!!!

IF ANYONE IS READING THIS AND HAS OR KNOWS SOMEONE WITH SERVICE MANUAL FOR R33 GTR THAT CONTAINS PAGES FOR FINAL DRIVE ACTIVE LSD SYSTEM PLEASE LET US KNOW

thanks for getting back to me man cheers.

Edited August 29, 2006 by mattymagoo22

[mattymagoo22]

actually I haven't checked if it the standard ecu..........

[MANWHORE]

Hey Paul!

I thought of an idea!

Since the diff is a mechanical diff, how about getting it shimmed, such that it's already preloaded a bit. Then when the oil pressure comes on, it'll be even tighter?

[paulr33]

the service manuls don't cover the alsd vspec system

ive already look in r32 r33 and r34 gtr and normal manuals, no mention.

they guys who opened up my diff said it didnt need shimming or any mech fixing to be done, he said the internals were perfect. im going to get my hydraulic line braided so its a new line and i can put a pressure signal on it

[MotoMan]

taking a keen interest in this as my new car also has the ALSD fitted...

97 R33 GTST

[waxer52]

Just wondering has anyone done any more testing on the a-lsd. Mine is only slipping one wheel since about two months ago.

[paulr33]

nothing further