Purchased a manual swap for my sc400, came with an auto tt lsd diff as well as a stock one, I want to rebuild the lsd and keep the other as a spare, I've read auto tt lsd has F2OSZ 2-1 on the back of it but cannot find out what diff the F2OS 3-1 is? Does anybody happen to know

The diff I received are:
F2OSZ 3-1
F2OSZ 1-2

 

Open the diff and check for lsd?????

 

I'd rather do it outside (raining here in Niagara) but I'm so impatient I think I'll make the mess in my garage I should see something like this correct?

 

Also curious as to what the ratios in each are

 

freebie https://www.clublexus.com/forums/sc-...d-and-and.html

please make note

 

Sorry.. was rushing I realized right after I posted in general sc3/4

Anyways popped it open and it is LSD. Still looking to find out what differential this is though as I can't find any info on a "3-1" I'm assuming a "1-2" is the stock ratio from a 5 spd sc300. What I'm really after is the ratio in the LSD

 

Count the # of teeth on the ring gear on the LSD, and the number of teeth on the pinion and usually that indicates the gear ratio.

 

Yes you''ll see teeth in the center of the diff where as an open diff just has a empty bar there.

 

Thanks for the help HiPSI, There's a 3.26 in the lsd and 3.76 in the open

 

Yeah if you see that you hit the jackpot you have a Torsen diff. The open diff is easy to spot because its just 4 gears in view with a big hole in the middle.

An open diff would look something like this inside



If you do get a Torsen though, from what I understand they don't need rebuilds. They either work or don't work. It's metal inside it can't "technically" wear. I don't even think you can rebuild a torsen.

If you get a clutch LSD though then you hit the jackpot because they are even more rare and more expensive.



Example of a Clutch LSD. These ones can be rebuilt. A torsen you don't need to, just flush the fluid and put some new fluid in and you're good to go.

And just to share after getting some JDM import shops near me to open up 3 diffs I finally found a Torsen diff. It was in a manual 5 speed N/A supra of all places... and the last diff available to open up. It was like hitting the jackpot! The owner of the shop wasn't pleased that I had him open up a diff and tell him that I didn't want it. He was super pissed opening up the other and when I saw the Torsen gears I just said "yup I'll take that one". They are hard to find! I got a steal on mine though for $400!!!! I saw some floating on ebay for $800-900 plus shipping ( and these things weigh a ton)... I'm super stoked!

 

Yeah I noticed it weighed quite more, one was torsen lsd and one was open, I got a wicked deal on mine as well! Basically came free with the sc400 m/t swap, he threw it in because his sc is for sale and would have no use for it. Very excited to get it all in, cleaned them both up and saving the open supra 3.76 as a spare