In the last month, I have started having occasional issues starting my 2004 Ford F350 6.0L. This motor is completely stock to the best of my knowledge. (except for coolant filter, which the previous owner installed that I continue to use and maintain)

This issue has only happened when I am running errands and the engine is warm/hot. It fires right up in the morning or after it has sat for a long period of time. When the no start issue happens, although it is frustrating, it does eventually start after sitting and waiting 5-10 minutes. During the problem the truck starts and stumbles quickly and then shuts down, there is no response if I press on the throttle. The fuel filters and fuel separator have been checked and replaced just to make sure (even though they were replaced 5000 miles ago.)

I have read recently that an oil leak of some sort may be keeping my thinned warmed up oil from getting the PSI needed to operate the system. I only have basic mechanic skills and tools and am seeking a starting point to start troubleshooting how to resolve this, or where to start looking for this leak (if that is a possible cause) with hopes I am not doing more damage by driving it while trying to fix it myself instead of taking it to a shop. Also, is there other things I should be looking into as possible culprits to this issues. Thanks for any assistance.