[Mahler9th]

I used Redline synthetic in my 915 for about 15 years without issue. My application is track driving and racing.

I used their NS version for many of those years.

No need for debate on tranny lube.

From what I have read, the fact that it seemed to shift find on a street run is perhaps most telling. Before opening up the 915 I'd want to check all four mounts carefully, as well as all of the bushings, et cetera. Really everything external, very very carefully.

Longshot... I'd also check the pedal box area very carefully to ensure junk is not under the clutch pedal. Back in 2002 I had such an issue at Laguna Seca. Wife and I had driven the 911 about 6 times by then, coming from a 951. I thought she was having trouble with the on/off RSR clutch. Wrong. It was crap under the clutch pedal.

She ended up #2 in the TT that weekend. The next time out she got TTOD overall.

After that experience I cleaned out that area after every event. Lots of crap under there, especially rubber. And that crap can move about.

I also bought my buddy a small shop vac as a bachelor party gift after I had my experience. He kept it in his trailer and we could all use it at events to get all the rap out from under the pedals.

Again, this is a longshot. Will think more on this situation.

Meanwhile I suggest more street driving to see if it can be reproduced.

Nice to see we have a Pelican in my home town, MKE.