I have a few questions trying to figure out and hopefully learn something. I'm having a hard time finding out if the rear diff for the awd is350 and is250 is the same model? I need to find out what rear diff it is on the awd is350. I also read somewhere that the frs/brz rear diff is a 4.10 and can go on an awd is250, so if the is250 rear diff can go on an awd is350, in theory it could mean that the 350 can have an lsd. Hopefully someone could answer to clear some things out.

 

https://www.clublexus.com/forums/is-...rom-is350.html

 

thanks I guess, I've read this already and the thread. I still need to know the part number and the thread didn't confirm that the pumpkins are the same for the 250 and 350, just the final drive since there's a chance lexus made a change on the rear diff for the 350.

 

They do not interchange. Whole different pumpkin! That said, IS250C is the same as 350. But this doesn't help you one bit.

Pictures are of IS350 diff and OS Giken LSD TCD.




Your options are ^^ or buying a RC-F or IS-F Torsen LSD and installing the Torsen unit in your case as they have 2.937:1 ratios vs our 4.08:1/4.10:1 350's...

 

It's not going to work cause the 4.10 rear diff needs to match the 4.10 in the front or else it'll mess up my awd system. Plus the awd uses a totally different drivetrain from the RWDs. 250 rwd, 350 rwd and awd 250/350 each has their their own.