Jeep runs, but no trans function

Hey all,
I took the jeep out with my girlfriend and we were drifting and having fun in the sand. No jumps. Jeep ran great the whole time. It got a little hot once but we calmed it down and it had NO issues. We went to gas up to go home and I checked the fluids. The oil and trans were both where they're supposed to be. The trans fluid was a little runny-er than I'd like but it always shifts fine so I didn't think it was bad.
I pulled out of the station and onto the road, went about half a mile. WHen I was accelerating through 40 mph there was a heavier than usual (the DS has a vibe around 45mph so I didn't think it was bad) then the vibe stopped no problem. About 10 seconds after that the engine felt like it just slipped off of the trans. I hit the gas and the motor just runs like I'm in neutral. I pulled off to a parking lot and looked under. DS's area all in and look good. There is no fluid leaking, and there is NO check engine light at all. I let it cool down and had a few whiskeys waiting for our ride to come and went back out before we left. It starts FINE no issues, idles great. Still no ck engine lights at all. I put it in gear and drove to the end of the parking lot. Put it in Reverse and nothing. It's like the engine is just there and it's not connected. Repeatedly starts with no issues and idles great like I said. THere was no boom or any sound when I lost power. It's strange.
Fluid? I thought it may be the output shaft or something but it moved under it's own power then just quit again. I'm going to have it towed tomorrow here to the house and get under it under good light and have a better look, and pull the trans pan to take a look under there.
This is a mystery. to me.
The motor is a NEW stroker with 1800 miles on it and the trans is, until now, holding fine in any driving condition.
I brought the jeep out to this same spot only a few days ago and did exactly what I did yesterday with no issues and brought it home.
Any help our guidance wouldbe great. Thanks guys.

you didnt say how many miles are on it, but its not uncommon to see a transmission completely crap out without giving any prior signs that it is. do you still have park? (you can feel it lock)

Same thing happens to me occasionally. Usually after I run it hard for a bit like you describe. I suspect the TCU realizes it's in trouble and does something flaky, then forgets this as soon as you reset it by stopping/starting the car, and if you're easy on it it stays working for a while longer. I've flushed my trans fluid (drain+fill, emptied the pan but not the valve body + torque converter, also emptied cooler and lines) and swapped out my TPS. Mine has been acting crappy for a while so I'm replacing all the seals/gaskets and filter on a good one I got and swapping it out, then I'm going to rebuild the old one and keep it as a spare.

Try unplugging the TCU or pulling it's in-line fuse (the yellow wire to the TCU) and try driving it shifting manually. You will have 1st in 1-2, 3rd in 3, 4th in D, park, neutral, and reverse--if the problem is electrical. If you do not have the aforementioned, then your problem is hydraulic/mechanical and it is time for a flush, or a replacement.

The "runny" fluid concerns me. I like my eggs runny, not my fluids.

Tcu makes no difference for this concern. Nothing electrical can cause a non-engage problem. I would verify the pump is working- engine off, check trans fluid level, then start the engine. The level should drop. Try that and report back.

deffinetly sounds like a fluid problem. I agree with JJacobs on the pump. I have a feeling you had the pump blow up. you mentioned having the vibe. Obviously it was something rotating, then it just gave out.
To me, You were driving, pump went out, thus no tranny fluid was being circulated, and then you lost all line pressure holding you in gear, and thats why the engine revved up as if you were in neutral.

I'm going to go have it towed today. I'll look at it and see how it acts before it's towed. I'm expecting a rebuild for the trans at this point. Anything less will be good.

Thanks for the hep guys. I'll get back here when I know something

It's got 140K on it. The fluid has about 25K at least.