Can someone point out the differences in the S4 clutch type vs the S5 viscous LSDs? I know how they work, but wondering whats the main differences in how they will act. Will you be able to really tell a difference? I have a stock S4 LSD in my GXL, and am about to swap in a 89 GTUs rear diff, for the 4.3 gears. I keep hearing alot of people say that the viscous sucks, and was wondering if that is true, and why?

 

^Bumpity..^

 

The problem with the viscous LSD is that it doesn't react fast enough. If you know how they work, then this should make sense. Since the bias torque by the viscous fluid slipping over each other, the LSD won't react until AFTER one of the wheels has already lost traction. When one weel starts slipping, the fluids take a while (relative) to match speed, so there's a delay. That's the main downfall of a viscous unit: Reacts too late.

 

clutch is better for performance, but on most FCs it's very worn. VLSD's on the other hand don't wear out like that and just have to have the fluid changed.
You can get clutch kits to rebuild the clutch LSDs.

 

is the performance with a torsen any different?

 

All I know is my clutch type is worn out, and will spin some but slips much more.

 

TorSens get torn up on hard launchs and will get broke if you dragrace with decent power.

I think clutchs are better, but I'm not positive on that.

 

I know the VLSD takes slightly longer to lock up, is it noticable though? Like on hard launches will I spin more?