Been here, done this...like 10 times..
Assuming the tach moves when you crank it..
You either ran out of fuel, or had a bunch of water in the fuel bowl..
Take the cover off the fuel filter, drain it, then have a friend turn the key on so the fuel pump runs..if the bowl starts filling immediately (You'll notice it) the pump is fine..Stop the fuel pump. Drain the bowl again. Now fill the bowl to the top with a 50/50 mix of diesel and
FPPF FUEL POWER
Pour the rest of the bottle in the tank.
NAPA should carry it, mine does.
Replace the filter, replace the cover, and cycle the pump 10-15 times without trying to start it...it wouldn't hurt to PLUG IT IN for an hour before-hand.
After the cycling, start it. Now run it easy like around the camp until it comes into it.
The tank on these trucks condense water whenever the truck is running..the warm fuel from the return line hits the cold tank, and...
You HAVE TO run a top quality fuel conditioner, a little dose EVERY TIME YOU FUEL.
FPPF is the BEST I have found.