Well, still acting up here, figured I'd post for some extra input...

Went out to log data on a warm day here, 85, had been driving around the city for a while so car was reading 90 on the display. First run in 3rd, Tip manual shift mode, shudders around 3,000 then pops into 4th around 4,500rpm, so much for logging, onto the problem.

Trans is 8 months old, upgraded A clutch pack after rebuild. Trans fluid flushed and confirmed filled to the top. Got some input from Tozo; I mentioned I had pulled the Aux radiators last year; he said trans fluid could be overheating/foaming and not being able to hold enough pressure to keep in gear.

Any other thoughts on why the fluid would be getting so hot?

Also for the first time got a trans code, scanned right when I got home; Trans Temp Sensor, reading implausible...hmmm, so that means it's hot I'm guessing, or just odd timing with a wiring issue. Car has full boost and more than enough power, too much apparently.

Also wonder if the notches we cut in the trimmed trans filter pickup might be adding to the fluid foaming? Don't know really. Thinking a flush with new fluid and filter, trim pickup just a bit this time, see how things look in there.

Just fishing, thanks for any ideas/input....