Gville350

iTrader: (10)

So would this "2GJ" carrier be a direct bolt-in for our 2IS? Sucks about the FD ratio being so low though.

I wonder if the new F-sport IS with the LSD option will be the same housing!

2013FSport

iTrader: (2)

It would bolt in direct but the 2.937 ratio would kill the 350 just like the ISF guys find the 350 gears too tight.
In short you're getting a finned case, lsd torsen carrier, a flange and cover. The 2.937 R&P would become a paper weight!

Gville350

iTrader: (10)

Yeah, all of the other OEM R&Ps are junk compared to our 4.09! The longer I wait, the more there will be on the market. One of these days I'll pop on one!

DickH

My biggest complaint with my IS350 is that it's missing a proper lsd. I'd swap out the differential if could get one cheap enough. Does anyone know if there is a truck/SUV option that would fit in our rear end?

2013FSport

iTrader: (2)

I have to say that after fitting the BFG G-Force Comp 2 A/S the trac light and @ss stepping out are pretty much a thing of the past. It takes a wet uneven surface to trully light them up. These Tires have great grip/traction. I also notice Dodge fits them to the high HP heavy beasts they make.

Having access to a lathe opens up the options for setting up a R&P from any case. An option is to make a basic spanner fitting the carrier bearing OD allowing one to measure pinion depth from an existing 4.08 and then once that is known, fit the gears to new case, shim to obtain same depth, set preload and drop in carrier getting proper preload, backlash, pattern and you're pretty much home free

WylieKylie

iTrader: (2)

If you think your new all season tires are that big of an improvement you should try some real high performance tires. The car still needs an LSD with stickier tires.

redspencer

iTrader: (1)

I agree. From the incremental suspension mods that I've done on my IS350 throughout the past decade, it wasn't until I installed the LSD that I learned there was so much more available grip/traction from the loaded outside rear tire that was being underutilized because of the OEM open differential.

Even Lexus test drivers were able to reduce an additional 2 seconds off their lap times at Fuji Speedway when the 2010 IS-F received a Torsen LSD (compared to their best times using an 08 IS-F with an open diff).

2013FSport

iTrader: (2)

As a DD there is a need to get some miles from these tires. Bottom line is the crappy Nitto Motivio that came on the car suck @ss and the tail constantly stepped out. With better tires I can a afford to wait for a better deal.

But if anyone wants to drift and make smoke, grab them Nitto's! Or the Federal SS595...

celsior11

Hate to bump an old thread.

I've got the 3is IS350, supposedly shares the same diff assembly as early is350 and ISF.

I'm past trying to find an Lsd option, our standard ratio is low 3.0, at this point I'd be happy to have even just an open diff that's readily available in toyota/Lexus that's high 3's

Anything that bolts in as a complete unit

I heard the brz/86 diff fits the 250 but our complete diff assemblies are different

2013FSport

iTrader: (2)

Whaa? Your car has an open diff.... it has an eLSD

celsior11

All 3IS I think pre 17' are an open diff, if it does have an electronic lsd it's not very good!

I would be happy to settle for an open diff with a slightly better ratio eg 3.7

RRRacing

iTrader: (1)

We have CUSCO limited slip LSDs, please contact us for pricing. We have these LSDs installed on our shop 3IS and ISF, and they are phenomenal. We setup each diff custom per the application.

Rafi

rt99

so will your CUSCO LSD fit directly onto an 06-12 is350 or will they need modifications done?

2013FSport

iTrader: (2)

Knowing the OS Giken case needs clearanced to drop in, I'd guess the Cusco is in the same boat.

An option (so I've been told) is to mate the ring gear and carrier inside the housing, torque the bolts in the housing before inserting the side bearings. One option may be to use a crows foot on the torque wrench with the bearings and carrier in place.

Because the Cusco unit will require maintenance, I would advice grinding the housing so the paired ring gear and LSD unit can be installed / removed as a unit.

2013FSport

iTrader: (2)

This doesn't answer your question but here are some pictures of an OS Giken opened up. Posts 130 and 137.
https://www.clublexus.com/forums/bui...nce-diy-7.html