Anyone use a Keisler Transmission ?

Yep it's like the converter is locked 100% of the time.

The day I got it all installed and plumbed, I fired it up. At idle, and the foot on the brake, I ran it through the PRNDL, to fill all the circuits, and it worked fine. Only problem was a drip at the fitting between a braided cooler line and a steel line (don't remember if it was supply or return). I tightened the **** out of the fitting until it stopped leaking. Turned it off, added a little fluid to bring to the correct level. Next morning, it goes BANG as soon as I dropped it into R, and it's done it ever since.

Initial Kiesler guess was too much back pressure in the cooling circuit. I reran the hoses after the braided lines, and put the radiator cooler and the aux cooler in parallel. Seemed to make it better, but could just be wishful thinking.

Next, the GM troubleshooting suggests the pressure control solenoid was bad. Replaced it, no difference. Also replaced the TC pressure control solenoid, no difference.

I've disconnected the TCU to run it in limp mode, and no difference at all. This ought to rule out electrical shorts, something mis-pinned in the harness connector, bad software, bad tune, etc....? (It ought to prohibit lock up in limp, and there should not be lock up in 1rst or R anyway even when the TCU is plugged in)

I was thinking about trying the TCC solenoid next, but the transmission guys say those usually don't fail while this new. A really good Transmission shop in Illinois suggested just looping the cooler lines together right at the barb fittings in the case. I have to loose the headers, pull the distributor and wrestle with some other **** to drop the tail enough to get at the fittings, so I've been putting it off.

I'm open to ideas!!!!

Thanks,
PH