98 Chevy Suburban 350 4x4 Stalls after warmed up????

~6 months ago I replaced the fuel pump and fuel relay.
In the last 10 days I have had two issues, one appeared to be a fuel and the other an electrical.

I replaced the fuel filter and that seemed to alleviate the sputtering problem I was experiencing.

I thought I had a battery issue but after testing the battery at two different locations, I replaced all cables and ended up having to replace the starter. That fixed my electrical issue.

But now I am back to running the car for 8-10 miles, it gets heated up (not overheating) and the car starts to sputter then will die. If I try to start it immediately it won't start. It will crank.
If I wait a few minutes (5-20) after it cools down a bit it will start. To be on the safe side I checked the new fuel filter and it's okay. I even replaced the fuel relay (again) to make sure I didn't get a bum part.
I am not sure where else to look, any ideas??