Hey guys!
Does anyone know where I can possibly find a new or used limited slip off a FRS? I've got a limited slip still from a fellow CL member that I bought off of like two years ago (and installed in my 2IS) but I was told that unfortunately the limited slip will not fit in the 3IS. I don't plan on spending much on it so that's why I mentioned above that I'm open to used LSDs as well. Thanks!

541 motoring sells low milege frs/brz differentials for dirty cheap. :eek2:

Would an FRS/BRZ diff fit the 3IS?

u have a few options here. I cant say it will mount up to your rear subframe because the bushings on the frs is round and the bushing on a is250 is eggshaped but I can tell you this. The final drive is different 4:1 vs 3:7 (oem lexus 250) you can take the frs unit and mount your ring gear and pinion gear to it. or you can take the frs carrier assembly with full guts and bolt it up. for an frs complete differential is a double upgrade, an lsd traction unit and a shorter final drive. the frs uses a is250 transmission with the exact amount of planetary teeth in every gear.. also the frs and is250 uses the same inner cv joint (diff mount) but different outter joints (hubmount). its called velocity type. both frs and is250 uses the same propeller shaft the only thing different is the frs uses a different outer/hub joint while the is250 uses the same velocity style outer shaft.


is350 have a slightly larger ring gear and a few more gear teeth than a 250. also it is a 5 bolt pattern propeller shaft. it wont work for is350.


you can look into is300 carriers for easy in and out swaps and a shorter final drive or use your final drive with a Toyota lsd for is250 owners


is350 owners might have to look further for is-f unit.


I gather up my information from my work computer at a Toyota dealership. I have access to all specs, procedures, illustrations, repair manual etc to Toyota scion and lexus .

Thanks for that info. TIS is wonderful to have at times :thumbup:

Would you be able to verify if the 2IS 350's ring gear / pinion will bolt up to the new 3IS 350's differential?
I've heard that it's about the same gearing as the ISF, but the housing is different from the ISF. Would be nice if the whole 2IS 350's differential would also just be a direct swap.

Thanks!

ok here.

2006 is350 have a ring gear size 208mm
12 teeth on the pinion gear
49 teeth on the ring gear

is-f torsen diff have a ring gear size 208
16 teeth on the pinion gear
47 teeth on the ring gear

3rd gen is350 have a ring gear size 208mm
15 teeth on pinion gear
47 teeth on ring gear

3rd gen is250 have a ring gear size of 205mm
11 teeth on pinion gear
41 teeth on ring gear

Scion Frs torsen have a "unknown ring gear size" not listed
10 teeth on pinion gear
41 teeth on ring gear

Stamped on Frs diff uses a FD20A but is listed as a FD20AT

is250's should have this stamp, so should the 3rd gen is250. both scion frs and 3rd gen is250 use a 3 piece type propeller shaft(shell cup type) and both share the same inner axle joints constant velocity type(cv type). i think 3rd gen owners are good to go with this one. It should be compatiable with 3rd gen is250.

I checked the differential cover on a 2014 is250 and it uses the same FD20A stamp like the FRS. :woot:

so my options are either contact the motorshop or get an IS300 diff for my third gen IS 250?

you will be wasting your time if you contact 541 motoring for information about the differential. they only sell the differential and have no info about the swap.


you don't have to get a is300 differential, its harder to find and it has a lot of miles on it. The FRS differential will be a perfect fit from the info I got from work, the only difference is the final gear ratio, it will make a noticeable change when driving in a straight line. better or worst IDK.




*

I apologize people. The inner axles are different design. the frs have a different cv joint type than the is250

so the pumpkin wouldn't be a direct bolt on to the IS250??

SARD Japan have the LSR available for 3rd Gen IS250.
You can pm me for details.