well, if you get the supra tt unit (which is the same as the rmm btw), it's about 1400. now the install is very easy though, about 200. so that's 1600. if you get the trd one, it's about 900 bucks, but the install is very hard, and it's going to run you for about 600 bucks easy. so that's 1500. final price come out about the same. and keep in mind, with the supra tt unit, you still have your stock one -- easy to swap out later

 

This is good advice.

Also, many if not most of the 1997-1998 Supra TT automatics did NOT have the torsen differential (limited slip) so it is easy to get a standard open differential. I bought one and then returned it after finding out it was an open diff. I had a couple others that had theirs for sale check and sure enough... open diffs also. Even if the car spins both tires... that is NOT conclusive as the one I bought spun both at the track (he had video).

One other thing, a torsen will work better in corners as it manages torque and varies the tire speed whereas a clutch type LSD will simply slip (limited) as the car negotiates the turn. If you apply too much power the clutches will try to spin both tires at the same speed (not good for cornering traction). The torsen is definitely superior there. In terms of absolute strength... the TRD is probably stronger but at our power levels it shouldn't be an issue but could be if you are buying one out of a Supra (some of those are making SERIOUS POWER).

 

yeah, i believe the 3.76 gear with lsd was only available on 94 and 95 auto supra tt? someone confirm on this? i remember reading it somewhere before but couldn't find that info anymore

 

I would advise buying a new one personally (if you can afford it of course). Besides possibly getting the wrong one as jbrady mentioned, I would be concerned about the condition of the diff. Since it is coming out of a car with lots of power and presumably driven hard, the wear or even damage might be an issue IMO.
On a component that is obviously this critical, I didn't want to take any chances with a used one. You might be able to find a good one though, just be careful!

 

You have the same line of thinking that I have. A used one is out of the question. You never know what condition that part is, maybe is wear out, you just don`t know. I , for one , am not making that mistake; I will get a brand new piece, and I`ll make sure am buying the right part.

 

One thing that bothers me a little is that I heard that : 1) with the 3.76 you are always getting the check engine light on when accelerating, and 2) in the highway you`ll be pushing 300 or 400 rpms more , so the gas will be a concern... I need some experiences about that. Is it true about the check engine light ? I don`t like that at all. 2nd question, how much more gas are we talking about here ?

 

I am not aware of the check engine light (CEL) problem as a result of the diff. swap. I have always thought that occured with the TC on the GS430 (occasionally with the GS400). On my car, I have never had this issue.
Yes, mileage may suffer a bit. Most of us who are modding our GS4s (and GS3s too) are not that concerned with mileage I think! Yeah, it would be nice to get 30 mpg when I'm driving 20k miles a year, but like they say "ya gotta pay to play"! I have never really checked the mileage before and after my mods, so I couldn't say. Even if mileage goes down a bit it's still worth it. Most, if not all, performance mods will incur a penalty at the gas pumps; primarily (IMO) due to the enjoyment of the enhanced performance.
If I had to guess, I would say no more than 1 or 2 mpg as a direct result of the lower gears. Maybe another 1 or 2 mpg as a result of...
STOMPING ON THE GAS PEDAL MORE OFTEN

 

Well, a couple of miles a gallon is not that bad , considering the upgrade on performance... I can live with that. About the check engine light, am concern too because I will be replacing the torque converter also with the Dragon converter, from Carson Toyota, unless I get a better deal somewhere else. Any way, I already e-mailed the guys at TM engineering , so I `ll wait for the reply with the price . I can save the install ; that I can do it myself. This engine light thing keep bothering me; can it be that it need the install of a trans cooler ? I got one and I am putting it on any way. Josey

 

The CEL has nothing to do with the trans. cooler. You should have no problem since you have a GS400 (same year as mine BTW). Almost all of the problems with the CEL are on GS430s.
For the TC, did you check on the other source I mentioned? They just finished a group buy on these a couple of months ago-they might be able to get you a good deal on one.

 

for the rear end, it will NOT put on cel on the car. the tc on the 430 will more than likely cause the cel to come on, on the 400 most of the time people dont have it, i have seen couple of cases where it came on.

and yes, it's higher rpm, but honestly, with all the long distance driving i do. unless you punch the car, i don't really see any significant degrade in the gas mileage myself

 

Future: I got a reply from TM; is $1500.00 shipped to NJ. Not bad, having in mind that I will be saving $500.00 or more in install, and, I will still have mine to sell or swap. Now, what about the TC ? Which one do they sell ? I would like the Dragon , that , as far as I know it is the best and sold by Carson. I would not want to get a cheapy mickey mouse one just to save $100.00 and then 3 days later have to buy the real thing all over again. Carson`s Steve sells it for $800.00 + shipping. What I am trying to say is, that , even thou I will like to save some money on the TC, if it is at the expense of quality, I will go for the Dragon. Please, let me know if is any good ; To me, quality is very important, and relaibility. I want to find out before I ask for price. Thanks so much for your help man. Josey

 

When people refer to the 2,800 rpm hi-stall TC they are almost always referring to the Precision Industries TC (Dragon model is for our cars). Several different retailers offer hi-stall TCs and as far as I know they are all the same one made by Precision Ind. I recommend reading the info on their site: http://www.converter.com/
$800 is a decent price, check with Todd @ TM Eng. too if you're going to get the LSD from him, maybe he can give you a good deal if you get both?
Also, check with these guys for the TC: http://www.jpimportz.org/

 

My understanding is that all 93-96 Supra TT automatics had torsen differentials. In 97 Toyota changed to a different style of torsen and it became optional on the automatic TTs for 97 and 98. The one I had came from a 98 and the seller swore the invoice showed torsen equiped. He had driven the car at the drag strip and it spun both tires. He was POSITIVE it was LSD. Unfortunately it was not and after extended conversation he apologized and refunded my money.

Now, some 97-98 automatics do have the torsen but finding one is not easy and basically requires removing the cover and a visual inspection.

BTW, all the 6 speed Supra TTs had torsens but the carrier and attachments are bigger and are not a bolt in for the GS400.

 

that's great info. the rear end and lsd options are indeed very confusing among all the supra years. a lot of people got ocnfused about what they are getting and stuff. i would defintely recommend people get the right stuff new, or unless you know the seller well and sure you are getting the right thing

 

TM also sells the PI tc!!!! i quote from them befor eand the price was pretty good! i am not going to disclose the price here, but it's good. since you got the lsd from TM already i am sure you can get a good price on the tc too

and install, nah, i think 200 is enough, coz' it's just bolt on.

oh and i have the PI dragon tc, i can't be happier