Maybe you should try seeing if the fuel pump is overheating. Does it still break down if your tank is more than half full?
It could also be a broken temperature sensor somewhere, but this is very unlikely. Its probably something that has to do with the fuel injection system.
We have a 2000 Jeep Grand Cherokee, 4.7L that keeps dying when it is hot outside. No warning, it is not overheating, there are no codes, and it doesn't matter what speed you're going. You can crank and crank and it will not start. You have to sit for 3-5 minutes on the side of the road, without cranking it and then it will start again. We recently just spent quite a bit replacing immobilizer, key sentry -still happening. We tried the whole screws of the computer thing that is posted in this forum - still didn't work. The thing is - it is ONLY during the hot part of the day. Never happens at any other time. Let me know what you think it could be. It's driving us crazy, and like so many of the rest of you, we're about to drive it off the cliff. PLEASE HELP!!