Recently I wanted to check my limited-slip diff on my 996 2005 GT3...
After I jacked both wheels off the ground and put it in gear, I was shock to see the rear wheel rotate in the opposite direction of applied hand rotated direction..!?! It was acting like an open-diff and not a clutch-type limited slip..?

I even went so far as starting the car and driving the wheels in the air. I was able to stop one wheel which made the other spin-twice as fastest - like an open-diff does.

Question:
1. Did all 996 GT3 come with clutch-type Limited Slips
Or did some come with a Torsion-Type diff, which might explain the Open Diff behavior...

Thanks
steve

 

Steve,

Clutch type and known to be weak My 2005 996GT3 went out in less than 5000 miles, alot of AutoX, and the warranty replacement lasted even less time. When I got 930mans GT2 the diff was shot so I installed an OSgiken diff which I had great luck with in my SCCA T3 S2000 race car. Very progressive lockup and operation is seamless.

http://www.osgiken.net/products/superlock.html

Peter

 

Would you recommend the OSgiken for an AutoX only car?

 

If the LSD is truly worn out.. how could it turn the wheels in opposing directions when doing the hand-turning testing?

 

After more research, it does have the gear pinions like an open-diff. So it does act like an open-diff if the clutch pack is worn out.

I guess the next question is .. do I go with Guard, OSgiken, or Porsche?

I know the Guard can be completely custom with Ramps up/down. How does OSgiken feel under braking?

 

Ian Stewart won the 2007 SCCA SS Solo/Pro Solo Finale Championship in my GT3 with a bad diff. I have hot run the OSgiken in my GT2 @ many AutoX yet but for an AutoX car only, a Quaife type torque biasing diff will work fine and has no parts to wear. The Quaife will fall flat on its face on the track especially during high speed braking where you need a locking under deceleration LSD to keep the rear from walking around

OSgiken works like champ under deceleration. The back end does not walk at all.

A good LSD will have both tires turning in the same direction.

Peter

 

We can repair and upgrade the clutch packs and ramp angles.

Diff failure is known on these cars- We have upgraded DOZENS!!

Let me know if you need more info.

 

a good diff: either guard or OSG
i wouldn't test LSD by turning the wheels. my logic is that if you can't feel a dead LSD, u probably dont need one.
for rear engine cars, LSD is most useful in decel. the wt in the back helps acceleration so without LSD, you are still fine. drive a cayman/box without LSD then drive a 911 without LSD, you will know what i am talking about.