Hi guys. Finally done with my LSD swap so I though I would share the experience. Subsequent swap should be pretty straight forward if anyone is interested. Also decided to make both upper arms in the rear and started testing one while the new clevis for the #1 arm is in fab.

http://figsengineering.blogspot.com/...-lock-tcd.html


Thanks Mike

 

This is an upgrade I definitely want to do in the near future, awesome write up! Thanks for sharing

about the drain plug... I guess ill do mine sooner than later.

 

Very nice! I have been thinking about buying an lsd unit, however for the price of the unit and installation i might as.well trade in my car for a 10+ IS F.

 

That was my thought initially as well however keep in mind that this diff unit is different than the Torsen unit found in the later models. These are true locking diffs and not torque multiplying differentials. So even when on a lift, both wheels will spin in the same direction instead of needing a differential torque event to activate the Locking mechanism.
http://www.osgiken.net/techcenter.php

 

Which also means at some point you'll be back in the diff to change the clutch packs out when they wear out.

What oil did you run in it? Shockproof?

Any reason you chose not to use a silicone sealer?

Also - did you check out the manual on TIS? There is a tool to spread the case a few thousandths so you can easily remove the snap ring. Sounds like you had quite a time getting it out with all the preload on it.

 

according to OS Giken, they have NEVER had a diff, even on race cars that required servicing. OS giken recommends you use their own fluid and no LSD additive. In fact they recommend royal purple over redline and since you have to replace it after the first 500 miles (or 10 hours of track use) they suggest a lighter fluid like the royal purple initially, and then switch to their 85/250 os giken fluid...

While it is a clutch pack diff, it's not a crappy clutch pack diff that needs service all the time, they shoudl be good for 100k miles or more.

 

Not so much the preload as it was the thickness of the rings and how much of a ***** they are to compress. TIS just suggests tapping the outer race to remove preload, but that is not what was preventing the rings from coming out. TIS pictures a compound snap ring plier which I could not find readily.

I ran Amsoil 75W 90 severe gear oil. OS Giken suggested a oil change after the first event. It is a clutch pack system but there are so many elements that the frictional surfaces are approved for longer life. The TCD unit they had on display at SEMA was a unit out of the Nuburgring 24 hr Endurance Race and they said it show little signs of wear.

As with anything its important for me to test the hype vs the actual performance. So far cornering dynamics are pretty wicked. I think the E-diff was also causing oscillation of traction that was feeding back into the suspension and disrupting certain damping scenarios. The car just keeps getting better and better. At the moment my thoughts are that any power added is just wasted if it does not make it to the ground. For those 08 and 09 cars out there this should def make it on your list. if you want to go fast and be predictable.

 

Hi FIGS,
Very nice write up! I read through the whole thing, I have to say I did not understand every step of it. From a practical standpoint, most cars these days do not come with mechanical LSD, and E-LSD is good enough even on tracks, how is the before and after in straight line and on the tracks would be an interesting measure for the success. Someone in your area can bring their F and compare may be.
Ash

 

I have a quick question for anybody with the OS Giken TCD.

My shop just finished installing my coilovers this afternoon and are starting to tackle the diff. My question is what additional parts besides the LSD did you have to buy/replace during the install...i.e. gaskets, clamps, bearings, etc?

My guy just called me asking if I wanted him to buy 2 new diff bearings because he wasn't sure if they would be damaged during the install and it will take a little while to order and receive them. Who here replaced their diff bearings or any other component during the install? Thanks in advance.

 

From my experience with other LSD installations, new bearings are a must. Makes everything so much easier

 

Hey Mike Its Don. While under my car this weekend I was thinking the exact same thing. Im probably gunna experiment with this idea too.

 

They make it easier but are not necessary. If the installer has a blind carrier bearing puller then the bearings will be spared. Only required parts are the outer axle seals and spring clips on the axles.
90521-34003-rear axle spring clip QTY 2
90311-47019-LH axle seal x1
90311-47018-RH rear axle seal x1

 

Its a world of difference in terms of overall stability and the application of power while in corner. The E-Diff has too much disruption in vehicle balance and causes the car to load and unload in a corner. The OSG allows uniform, linear power application and acceleration through the corner out making it a much better experience.

 

Thanks for the response. My guy was able to get them out without issues today so I told him to keep the old bearings

 

Reading this thread makes me want to order one more & more...