So I was at the track this past weekend and noticed that a few times on a 4-3-2 downshift at the end of a high speed straight, I had a grinding feeling in the transmission on the 4-3 downshift. I also had this happen a couple of times on a 2-3 upshift. I noticed that if I took my time on the 2-3 upshift I wouldn't get the grind.

No 2nd gear pop-out issues. Car is a 03 996TT with 31K miles. It has a B&M SSK, new stock clutch and accumulator at around 29K and fresh Delvac 75W-90 in the transaxle. This is the second track event with the car. Car was never tracked before (I'm guessing on that one). The car is also CPO but I am not sure if that will help with this.

Driving on the street is fine as long as I don't rush the shifts, which I have a tendancy to do says my old Skip Barber instructor

So am I headed for trouble here?


Thanks all.

 

clutch accumulator

 

I too have the 2-3 issue if I shift very quickly so for now I've been babying it. Is this an issue of the clutch accumulator mentioned above or just inherent in the tranny's design?

 

I forgot to mention that the accumulator was replaced as well at the time of the clutch.

Still think it is the accumulator?

 

I also had a 3-2 shift problem with grinding during agressive downshifts but no problem with normal driving.

You may be surprised that mine was fixed by a tranny oils change. My tranny oil had never been changed (45K mi) and was thick and dirty (had all the factory maintenance work done). Turns out dirty oil affects the synchros ability at high revs.

After the oil change I still had the problem for about 100 miles and then the detergent action worked and now no problems at all.

BTW... at first I thought the worst... synchros... clutch... accumulator... etc.

Try an oil change first...

 

I had just changed the oil to Delvac 75W-90 right before the event and probably drove at lease 100 miles to the track so I'm not sure that is it. Maybe I'll drive some more on the street and try again. I just don't want to make it worse.

 

Any advice on synthetic brands for the tranny? I usually use Redline or Royal Purple. Hope your problem ends up being something simple like fluid triple

 

The Delvac 75W-90 that I am using is synthetic and is highly recommended for the transaxle.

 

did you ever get resolution to this?