2004 4l80e hot trans on hills

On my previous 02 6.0 4l80e, thenTC began to slip and would not lock up in 3rd. My tranny during this was running hotter then normal and had been for some time. I had it looked at and discovered that during a few years, gm installed some defective TCs which would crack and lose fluid. Sure enough when mine was pulled that was the case. So while it was already out I had the whole tranny rebuilt with a shift kit for around 1700.00. Afterwards even with the stock cooler, it never ran hot, and I never saw it go above 205 even pulling heavy. This was my experience, otherwise the 4l80e is really stout. In fact when we checked the forward clutches, they were barely burnt/worn. But I knew the TC was shot so it was just a few more bucks for a compete rebuild. Anyway good luck on your search. Mine had about 160k when I had issues. Only have a trusted shop look at the tranny and show u the issues if any.