B16da9

iTrader: (7)

I just wanted to start a thread about my swap for an IS300 Torsen LSD. However before I get to that I wanted to give member Jeff Lange a thank you for doing all the research and being the guinea pig for this mod as without his knowledge this would have not been possible.


I haven’t installed the LSD carrier diff in my car yet but I just got the Diff. today by FedEx and wanted to share some pics before cleaning it up and installing it.

Kingdavid

iTrader: (1)

I'd love to see a storyboard for this, from lift up to lift down.

badx33

iTrader: (53)

Hey don't forget to call me when u do this swap..

Hoac

Hell yea!

I agree with the above poster, I wanna see what all it takes to swap it out. Been thinking about getting an LSD but I am a big DIY'er and never done a differential swap before.

Kurtz

iTrader: (1)

First you will need to trade your car in for a 250, since it doesn't fit in the 350...

Hoac

sigh

I've seen this one out there for the 350

http://www.dezod.com/pd-os-giken-limited.cfm

But for over 2 grand I think the money would be better spent elsewhere.

Does anyone have the Dezod LSD? Any comments about it?

GiantsFan

iTrader: (9)

You want the ISF LSD for the IS350

(Please correct me if I'm wrong lol)

Jeff Lange

iTrader: (1)

While it seems likely that it may fit, confirmation on ring gear diameter and bolt spacing has not yet been had. From Lexus the IS F Torsen is even more expensive than an aftermarket LSD. Need to wait for some IS F's to crash first and then do some measurements. Seems like that might be a while.

B16da9, if you haven't thought about it, I'd suggest also replacing the breather before you put it in. Cheap insurance against seal failure in the future.

Jeff

B16da9

iTrader: (7)

That is correct, this mod is for the IS250 only.


The information bellow was compiled by member "Jeff Lange".




The IS300 uses the same differential case/setup as the IS250 RWD and 09+ IS250 AWD. The 06-08 IS250 AWD uses a smaller diff and the IS350 uses a larger diff (same size as the IS F):

01-05 IS300 models have a 205mm rear differential

06-08 IS250 AWD models have a 190mm rear differential (A Torsen from an IS200/RS200 Altezza might work well in this application)
06-11 IS250 RWD & 09-11 IS250 AWD models have a 205mm rear differential (The IS300 Torsen is a bolt-in upgrade for this application)
06-11 IS350 and IS F models have a 208mm rear differential

If you want to do this, what you'll need is an 01-05 IS300 differential with LSD. They come in either 3.73:1 or 3.91:1 ratios, same as the IS250 does.

There are various ways to tell what diff the IS300 has, depending on what information you have. There is the axle code on the car's information label, the sticker on the differential, looking through the axle hole, or pulling the diff cover off. As it is a Torsen, you cannot simply just turn one side and see if the other spins the same way or something like that, as without load the diff will act like a regular open differential.

On the IS300 information label, the axle code will be listed:
B01A = 3.73:1 (MT) Open
B01B or B01C = 3.73:1 (MT) LSD
B03A = 3.91:1 (AT) Open
B03B or B03C = 3.91:1 (AT) LSD

On the IS300 differential sticker, the code will be listed: (My sticker was so old, it could no longer be read, so I had to check the actual diff inside to confirm)
M82 = 3.73:1 (MT) Open
M86 = 3.73:1 (MT) LSD
M96 = 3.91:1 (AT) Open
M98 = 3.91:1 (AT) LSD

B16da9

iTrader: (7)

Thanks Jeff, I'll add that to the list of seals and misc. parts that I need to buy for it.

Gville350

iTrader: (10)

There is hope though for us 350 owners, but the costs are alot more. Either a Giken, Quaife (cheapest option at $1k), TOMs LSD, or what we have yet to confirm...a 2010+ Torsen ISF LSD.

One day I hope to pick up a used 350 pumpkin and replace it with either a Quaife or a used ISF unit.

Joe Z

iTrader: (10)

Great thread...!!!

Not sure if you most of you guys know this, but the new Toyota GT86 / Scion FR-S will also have the IS300 Torsen LSd unit..





**** I'm sure Jeff knows..

~ Joe Z

Gville350

iTrader: (10)

^Those pics of a stock FR-S right there...is that Red Permatek high temp sealant? LOL! Wow.

Good info though! Glad to hear that the unit is that reliable that they are using the same design/LSD unit in these brand new vehicles.

Jeff Lange

iTrader: (1)

The sealant would be Toyota/ThreeBond 1281, which is what Toyota uses on all their Differential/Transmission/Transfer cases. It's actually orange though, not red.



I'm waiting to see part numbers, there is the possibility that the 86/FR-S will be using a different torque bias ratio than the IS300, but probably not. Still would be curious to know. Still, there may be some IS owners buying some Scion parts to put in their cars .

Jeff

Hoovey689

iTrader: (16)

nice pumpkin!!