Truck will not start

"Tries to turn over but it won't crank" -- so the engine does not crank over at all? Or it cranks fine and doesn't start? No crank is likely a concern with the engine's 12 volt battery. It's either low in charge or unable to handle a load. As far as stalling while driving - this is another issue altogether, and will require engine performance diagnostic testing. Too hard to know without hands on testing.