tonythe93sc400

I've seen this discussed at length in other threads, but I wanted to confirm it again.
Is the 93-98 Supra TT 200mm Auto LSD a direct bolt in modification for our cars?
Entire diff and all?
Does the case need to be trimmed?
Do the axles have to modified to bolt up to the diff?
Does the driveshaft flange have to be changed or modified?
I've read it's a direct swap but I've also heard you have to trim or shim various things to get it to work.
What is the actual consensus from people that have done it?

KahnBB6

iTrader: (5)

Indeed it is. I have a 200mm Supra MKIV TT Auto Torsen installed in my SC300. It is quite literally a direct bolt in except that you must swap on an SC300, SC400 or Soarer Z30 diff companion flange (and don't use an impact gun to do it! Follow the TSRM instructions for our 200mm diffs as to the companion flange installation). Otherwise everything else fits exactly the same as a stock SC300, SC400 or Z30 Soarer rear diff.

The ratio for these is 3.769:1 so make sure that will be ideal for your engine and transmission combination. And since Torsen LSDs are not possible to 100% verify externally since some Supra TT auto pumpkins came in 3.769:1 open diff from 1997-1998 the seller needs to open the rear diff cover to snap some pictures of the inside proving that there is a Torsen T-1 (or rarer T-2) in there before replacing the cover and re-sealing it.


The entire diff and all with the exception of the companion flange which needs to be swapped for one from an SC or Soarer. The Supra MKIV and GS/Aristo 200mm diffs use companion flanges with 111mm spacing. The SC300, SC400 and all 1991-2000 Z30 Toyota Soarers use rear diff companion flanges with 101mm spacing.

Nope! It's the same exact diff pumpkin/case with the same exact dimensions. It's just that the Supra MKIV version has some additional cooling fins in the iron casting.

Your stock SC axles will bolt right up. I have heard that perhaps for late model year SC's some earlier model year axles will need to be swapped over... but I've never seen or heard anything conclusive regarding that and everyone else I've read about who have bolted up a 200mm Supra TT Auto LSD diff has not had to swap any axles to get it installed correctly.

The SC driveshaft flange and OEM rubber donut do not need to be changed, no.

This is considered a direct swap. Again I think the most I've ever heard of needing to be changed besides the diff companion flange is perhaps swapping a set of Supra MKIV 200mm diff axles or earlier SC model rear diff axles in a very few cases. So few cases that its very rare for anyone to need to do.

Now if you were planning to install the Supra MKIV 6-speed rear subframe and 220mm rear LSD diff then there would be many more parts that are required to be swapped over. But not really much with the 200mm TT Auto diff besides the SC/Soarer companion flange swap.

Hope this helps! : )

tonythe93sc400

This helps very much! Eventually, I am planning a 6 speed swap. For now it's just the automatic.
Do you have a link or part number for the companion flange? I've never had to swap one before, so I'm not entirely sure what I'm looking for.
Doing a quick search, I found a new 41204-30040 part number from Toyota/Lexus. This may not fit my 93 SC exactly, but is this the part I'm looking for?
Again, do you have a part number or link to what you used, since you know it works?

KahnBB6

iTrader: (5)

Glad to help!

I don't have a companion flange part number, sorry. Usually we just take one from a used SC differential. Even if Toyota still has some of those in stock to sell you'd be receiving one in bare metal which you'd need to get powdercoated after masking off the areas that are meant to be exposed/unpainted.

I would just take the one off your SC's stock differential assuming you'll not be using it again. However Tremec T56 6-speed Magnums tend to like 4.272 or 4.083 ratio diff in these cars but those transmissions will work with a ratio as low as 3.916:1 (SC400 ratio) or the TT Auto 3.769 ratio. It depends on how tight or long you want your gearing.

If you will be performing a Nissan CD009 6-speed swap you'll ideally you'd want a 3.266:1 200mm diff. You can find these from SC430's among other cars. The companion flange swap is also needed for that specific diff casing swap.

Keep in mind your long term build plan as to your LSD choice. The Torsen T-1 is a good all-around LSD for lower power applications (NA or turbo). My 2JZ-GTE SC300 makes a very mild 350hp and that's well under the T-1 Torsen's limits. At 450whp-500whp or higher another much stronger aftermarket LSD will be needed for longevity. Or a stronger (and super rare) OEM JDM T-2 Torsen LSD that fits our 200mm diffs

The T-1 also isn't a great drag racing diff and won't handle super abusive launches on slicks constantly. But... as a normal performance road car LSD it's still very good.

All this is to say that even if the 3.769:1 is the ideal fial drive ratio for your 6-speed swap and overall build, just consider the power level you are going for. You may be better off investing in a Kaaz, Cusco, used TRD or new OS Giken Super Lock as your LSD.

The 3.769:1 ratio was also available in the Toyota Aristo (JDM GS300) when factory equipped with the 2JZ-GTE engine (auto only in those cars) which also had the Torsen LSD optional or standard depending o the Aristo trim level. The 3.769:1 also was standard in the 1996-2002 JDM Supra SZ-R 6-speed naturally aspirated models.