elh0102

After reading the posts on testing the differential, I did the test of jacking up one rear corner and testing for wheel movement. It moved with relatively little effort which, as I understand my reading of this, would indicate it to be faulty or worn out. I know that is not the case, based on my feel of the car when driving. While I had one rear corner slightly lifted with a floor jack, I started the engine and gently released the clutch to the friction point. It clearly was beginning to engage, and from the feel, I'm sure I could have driven off the jack, but obviously I did not. So, I am now certain the differential is functional, although I am sure it would show wear upon inspection. Anyway, the previously discussed testing process seems only a rough guide, at best. Anyone had similar experience?

996FLT6

I found out my LSD was fried when I took it to the track but driving in the street never felt an issue. Driving in the street is pretty transparent. Mike

Steve B in SD

Mine makes a barely audible clatter under light acceleration around corners. From what I understand, that's normal, and an indication that everything is fine.
Does yours make any noise that you can hear?

Erik@GBox

The normal test that you have done to check the differential for wear may not quite apply to your particular car. We have noticed that Porsche has lowered the Pre-Load on a lot of their differentials, relying on the ramps to generate the needed pressure for lock-up. Your differential could be quite healthy. I would simply inspect the internals to confirm that they are in good shape, and then make the call from there. Be careful taking the differential out and putting it back in. If you ding the ring gear against the pinion head you might find that you have a whine after reinstallation.

Personally though based on what you have described, I would not worry about it. Sounds like it is working just fine for a street application.

Hope that this helps,


Erik Johnson
GBox Performance Transaxles
(303) 440-8899 work
(303) 895-4828 cell

Holger B

My experience--drive in reverse slowly and make a tight 90 degree turn, the turn won't feel smooth like a car with an open diff and there will be some noises coming from the LSD. If that happens, you're fine.

elh0102

I think you're right. I took the car out tonight, both through some on-throttle 2nd gear cornering (wanted to have enough torque available to test traction) and parking lot turns, and the diff is working. I'm sure the lockup specs would not be ideal for serious track work, but my track time these days is very casual, so I think it will be fine for a while. And mine is an '05 model, so maybe there were some late model changes, as you suggested might be the case. Think I'll worry about a better bourbon and forget the differential for the time being.

Erik@GBox

I'm a scotch man myself, but I am glad that I could help. Let me know when it ends up going south, and I will be happy to help you with a new differential, there are several good ones available these days.

Erik Johnson