03 tranny fluid leak problem

On my 03 1500 suburban 4x4 the tranny finally gave up at 249k. I had a rebuilt tranny installed and after about 1k miles I'm driving down interstate look ;in my rear view mirror and smoke is rolling out of the rear of the truck I look like a crop duster going down the road. I stop check under the vehicle and tranny fluid is raining down from the bell housing area onto the exhaust I get back in notice my tranny temp is about 20 degrees hotter than normal so I put it in gear and limp to the next exit about 2 mile the tranny shifts normally the only difference is fluid 20 degrees hotter once I get off exit while waiting for tow truck I look under truck with engine running from bellhousing back is covered in tranny fluid but I see no fluid leak anywhere. any ideas on what's going on here?

Tough here to suggest a source of the leak without an onsite inspection. Cooler lines are one possibility.

Just about always a cooler line- corroded and broke- same thing happened on my Dually....had to splice in a temporary hose fitting until I could get home and replace the entire lines.

With a fresh rebuild and hot trans, it could also be the vent line burping oil.

Ok here is what I did yesterday after truck sat all night checked fluid nothing on stick filled fluid back up to full it took 1 quart got underneath truck wiped down all traces of fluid with truck running did not see a leak anywhere put cardboard underneath let truck run for 20 minutes there is a slight leak coming somewhere on passenger side above exhaust crossover pipe I cannot tell where it is coming from as the only drip I see is underneath pipe on passenger side of truck.

if has happened before after a tranny job the fluid lines may leak running to the radiator ....see if they are loose use a line wench ..don't over torque the fitting ..

maybe tough to get at ..on tranny pass side..