theman

To the dismay of many, Toyota cheaped out on their top tier car's base level, not giving it an LSD standard in the Lexus SC and Toyota Supra Non-turbo.
So looking through the online data people have compiled good lists of Supra and SC rear-ends. I decided on snagging an Aristo turbo auto JDM LSD, it has a ratio just a tad lower than the tall-ish stock gearing in the Supra 5spd and near that of the Supra turbo auto. Makes for a nice match with the 5spd for future turbo application.

This swap should be very much the same in both the SC300 & 400... as if I recall correctly the sc400 came with the same auto tran of the Supra turbo automatics. You may not even need to swap the yoke in that instance, but I haven't done a hands on in the 400 yet so not for certain.

Some pics... First old dirty-open diff.


Comparing the diffs...
Aristo turbo JDM LSD on left, open NA on right.
Install Note: You must swap the yokes to use the NA driveshaft to this heavier Aristo LSD, just as on a 6spd turbo Supra. The swap is easy, just zip off the bolt using a deepwell 36mm on both... just remember to torque the 5spd yoke back onto the Aristo diff using the higher 6spd turbo rear torque specs.


One other good idea to do during the swap is to add in the turbo Supra 6spd secondary Diff mount in the rear subframe. This and the LSD should cure any major wheel-hop along with much better oversteer characteristics after the install of a proper rear-end.


The car feels night and day different now... much better response, and even with the slightly less aggressive gearing seems much quicker off the line due to no one-wheel-spin action.

xtra

Congratulation on the upgrade, I don’t want to sound pessimistic but “how do you know it’s LSD “. The only way to tell is to open the pumpkin to make sure the torsen disks are present.
I am bringing this to your attention because I purchased a supposedly LSD aristo diff from a local importer, after installing it, it turned out to be an open diff. I took it out, brought it back to them. They gave me another supposedly LSD diff from the aristo. Upon arriving at the house, I opened the pumpkin to make sure it was LSD. Needless to say, it was again an open diff LSD.
I went back to the importer and he refused to take the diff back nor giving my money back, his excuse that was I may have swapped the LSD unit in the pumpkin and was trying to pull a fast one on him.

I am still seeking a LSD diff for my SC but currently using the aristo diff, the gear ratio is amazing and saves a lot of gas while cruising 5th gear on the highway.

PseudoK

would MK3 supra diffs work?

blk&blu*j

iTrader: (1)

NO and NO!!!!

theman

xtra - You don't have to even open the diff if you are familiar with torsen diffs... there is enough grip drag in the diff that when you manually turn one wheel/axle the other side will rotor in the same direction. If you have an open diff, the opposite side turns in the opposite direction. You can also turn the input yolk to check, so LSD will turn both output-flanges/axles/wheels, whereas open diff only spin one output-flange/axle/wheel. But sure, if you like you can always open it up.

I grabbed mine off a reputable ebayer, and doublechecked his method for LSD determination... I had paypal/ebay backing me should anything not arrive correctly, and I doublechecked as well when it arrived before installing. You won't know how strong the diff works until under full power in the car, but at least you have a basis of operational status. Mine works great, and I've had plenty of LSD equipped cars throughout the years to know how it should feel on the street.

PseudoK

Is everything they built for the MK3 supra just junk then? there seems to be much hate of MK3 supra parts.

Maserati

iTrader: (1)

It's not a direct bolt on, you would have to do custom work to get it to work.

KahnBB6

iTrader: (5)

MK3's have a lot of great driveline parts. They just don't apply to our cars once you go farther back than the R154 transmissions we like to take from those chassis.

MK3 rear diffs are directly compatible with many other vehicles through: Toyota Cressidas, IS300's, 2nd gen IS250/350's, Scion FR-S's & Subaru BRZ's and of course any of the JDM only sport sedans: Chasers, Mark II's and Crestas. Don't know about Verossas but it wouldn't surprise me.

PseudoK

what about the internals swapped into the SC400 Housing?

theman

No go there either... and I second the no hate for MK3 drivetrain parts... they are quite robust, just more of a pain to adapt to the SC than worth the trouble.

Ali SC3

iTrader: (10)

they are not compatible differential parts it has nothing to do with hate or love.
now if you wanted to swap that mk3 diff into a pickup truck you would get a positive result because they use the same type of internals, but the mk4 and SC use a newer type that is much stonger built.

PseudoK

has there not been another car that uses this newer type then? no IS or GS?

hmhatch

iTrader: (1)

2nd gen GS has the same style diff but none came with LSD. Read above for IS info.

xtra

Yeah, except that this trick does not work with Torsen diff. It does work with mechanical, clutch style or viscous style but not Torsen.
Look it up , I have done a lot of research lately on toyota diff before buying my next one and the only sure way to make sure is to open it up or match it up with a VIN#.

However, i will agree with you when you said, driving a car with LSD feels much different then a car without.

Ali SC3

iTrader: (10)

actually I forgot the is300 uses the same setup as the mk3 supra, so you could swap the lsd from a mk3 into an is300 somewhow, I have heard of that being done.
The GS is the same as the SC and the LS with the newer style diff.
GS or LS will swap into an SC with changing the front part, the IS and mk3 are not compatible.