When it stops running, does the electrical die as well, or is it just the engine? This is reminiscent of an issues the LB7, LLY, LBZ. LMM, and LML's used to have when the housing the filter mounted to would get a hairline crack and air would get in, causing a loss of prime. My BIL had a LLY, we were going camping, both pulling 5th wheels. Before we left he mentioned every now and then, out of the blue, the engine would stop running, like you ran out of diesel, but would restart, he said the stealer couldn't find the issue. We made it to the campground, which had a 4 mile 10% grade just before the tirnoff, went up it no problem at all. On the way home, on I5 in the Central Valley, his truck dies, he starts it back up, keeps going. We get home, Monday morning I ask my mechanic, he said check the fuel filter housing, if anyone overtightened the filter, probably has a hairline crack, he said you won't see any diesel residue. My BIL picked one up, replaced it, never had it happen again. I would check the seal on the fuel filter, or just replace the filter, comes with new gaskets. On the filter housing cap, most don't know it's there, but if you look in the center of the borrom of the housing, where the 36 mm socket is used to loosen and tighten the filter housing, dead center is the Water in Fuel drain, it uses a T40, most don't know it's there, but that is what that is for. If you get a Water In Fuel sensor code, that is where you drain the water out of the filter.