How Do I Tell If My Diff Is Fcuked?

[jarrod83]

yeh i was aware of that... which is why im really tryin to get it the a-lsd workin.. otherwise i was going to find a r33 being wrecked and hopefully replace the diff centre and the axles... i mentioned it a few posts back..

[R31Nismoid]

Are you talking about your GTR diff^^^^?

Ive got some stock R33 gtr dumps if you want them. Theyre the cast things off the back of the turbine housings arent they. Just to clarify.

HR31 Diff, but same principle

[Beer Baron]

yeh i was aware of that... which is why im really tryin to get it the a-lsd workin.. otherwise i was going to find a r33 being wrecked and hopefully replace the diff centre and the axles... i mentioned it a few posts back..

the clutch packs upgrade are for the mechanical type LSDs as found in 32 GTR not the A-LSD you have. yours may have clutch packs inside (i'm not 100% sure) but what it has is a friction fluid and a pump to adjust the fluid pressure, that's what makes it 'lock'. I don't think the nismo clutch pack upgrade will work in the A-LSD. often the problem is maybe the fluid needs changing, or the pump is worn out, or something else in the diff is worn out. I've never been a fan of the active LSD. too unpredictable, the last thing you want in a diff is it deciding to lock or unlock at various times, you just want it to operate the same way every time so you know what's coming!

[FineLine]

the clutch packs upgrade are for the mechanical type LSDs as found in 32 GTR not the A-LSD you have. yours may have clutch packs inside (i'm not 100% sure) but what it has is a friction fluid and a pump to adjust the fluid pressure, that's what makes it 'lock'. I don't think the nismo clutch pack upgrade will work in the A-LSD. often the problem is maybe the fluid needs changing, or the pump is worn out, or something else in the diff is worn out. I've never been a fan of the active LSD. too unpredictable, the last thing you want in a diff is it deciding to lock or unlock at various times, you just want it to operate the same way every time so you know what's coming!

The alsd does have clutch packs, We have mine apart atm. I want this diff working again as its a far bigger stronger diff than the stock gtst number but its around a thousand bucks for a new clutch pack.

That may sway me to replacing diff and half shafts too.

[jarrod83]

fineline can you find out if it has the same clutch packs as the normal gtr diffs for me, i have changed my fluid on mine completely using both the bleeders..also what sort of condition are your clutch packs in?

Im also tryin to get mine working again, from what i can tell the lock between left and right wheels may be pressure dependant, meaning when there is no pressure all the power goes to the left wheel and as pressure is feed into the right side of the diff the power is transferred to the right wheel, and varying the pressure into the diff varies the torque distribution .. im basing this on that theres only one oil pressure feed into the diff and a feed that links them together.. It's really just a guess i may have to pull it apart to understand it more.. only other way to control the torque split would be electronically,

It's stupid the Japanese didnt make no v-spec manuals

I do agree with beer baron tho the unpredictability makes It pretty hard sometimes, when your drifting right it over steers heaps and to the left it under steers so much you end up doing a 3 lane drift

[FineLine]

fineline can you find out if it has the same clutch packs as the normal gtr diffs for me, i have changed my fluid on mine completely using both the bleeders..also what sort of condition are your clutch packs in?

Im also tryin to get mine working again, from what i can tell the lock between left and right wheels may be pressure dependant, meaning when there is no pressure all the power goes to the left wheel and as pressure is feed into the right side of the diff the power is transferred to the right wheel, and varying the pressure into the diff varies the torque distribution .. im basing this on that theres only one oil pressure feed into the diff and a feed that links them together.. It's really just a guess i may have to pull it apart to understand it more.. only other way to control the torque split would be electronically,

It's stupid the Japanese didnt make no v-spec manuals

I do agree with beer baron tho the unpredictability makes It pretty hard sometimes, when your drifting right it over steers heaps and to the left it under steers so much you end up doing a 3 lane drift

My knowledge at this stage is very basic Jarrod. I believe from looking at the diff that what you are saying is correct. I have a diff mob up here going to take a bo peep at it with a view to shimming the clutchpak to extend its life so I'll wait for the verdict.

The other idea I find very intriguing, When the giant boys (russel and Mark) purchased the 33 they are building it came with a manually operated ALSD. The system from Russels description over the phone involves the use of a drift style hydraulic handbrake with a master cylinder and a cock to lock off the return when the desired pressure is reached.

In other words, pump the hydro handbrake to whatever pressure you determine and hold it whilst you turn off the cock to stop the pressure bleeding back off and hey, PRESTO!

It sounds simple enough and once you determined the amount of pressure required you could set the diff as a 1.5 way or 2 way etc.

If the diff boys tell me the clutch pack in my diff is acceptable I am going to explore this option further. An added bonus would be the removal of the motors pumps etc that drive the diff.

[jarrod83]

yeh ill be interested to hear more about this, sounds like a good idea.. maybe theres another way to pump up the pressure with the use of a switch to turn it from one wheel to lockd.. definately sounds like its not a problem with the clutch packs themself slipping.. either a sensor or pressure problem.. going to take it for abit of a spin tonight to see if theres an improvement since i flushed out the hydraulic fluid from the diff

[cerci]

jarrod, try asking Moanie on here about her car

she has an r33 with alsd and got rid of it and now has a good mechanical diff at the back end

i would give up on the alsd, its an expencive hi-tech heap of shit pretty much, even when working "like it should" it will dissapoint 90% of the time

[jarrod83]

Ill try and work out how to give her a msg to find out what she needed to replace.. but i have to disagree with you cerci back when i first imported my car when she was near new like.. the active lsd was a joy to drive.. its hard to describe but you could thru it so hard into a corner n it drift lovely.. and when cornering hard it seem to power the outside wheel more n get you around more easy.. but if u do just lock it, its going to lose that capability

hopefully my cousin pikd up this wreck r33 for a engine swap his doing and i was hoping to pick the diff up from that.. but i want to at least attempt myself to see if i can get this diff working before i junk yard a 5000 diff ¬_¬

they do a good job tho at preventing troubleshooting of this diff =P

Cheers for the advice tho guys

[tacker]

any idea where to get the nismo clutch packs? Want to give those a try before i try a complete new centre

[bigmikespec]

My knowledge at this stage is very basic Jarrod. I believe from looking at the diff that what you are saying is correct. I have a diff mob up here going to take a bo peep at it with a view to shimming the clutchpak to extend its life so I'll wait for the verdict.

The other idea I find very intriguing, When the giant boys (russel and Mark) purchased the 33 they are building it came with a manually operated ALSD. The system from Russels description over the phone involves the use of a drift style hydraulic handbrake with a master cylinder and a cock to lock off the return when the desired pressure is reached.

In other words, pump the hydro handbrake to whatever pressure you determine and hold it whilst you turn off the cock to stop the pressure bleeding back off and hey, PRESTO!

It sounds simple enough and once you determined the amount of pressure required you could set the diff as a 1.5 way or 2 way etc.

If the diff boys tell me the clutch pack in my diff is acceptable I am going to explore this option further. An added bonus would be the removal of the motors pumps etc that drive the diff.

Fineline & Jarrod,

How did you guys go with your A-LSDs? What did you end up doing?

Mine in my R33 GTR Vspec is open wheeling major. I was thinking of replacing the whole bloody rear diff with a standard GTR one.

Mike