Step one is always to read and record the diagnostic fault codes. The people at most auto parts stores will do that for you for free. If you cannot get the truck there, you will need a simple code reader to read the codes yourself.
Do you have a 5.7L or a 6.5L? The 6.5L is a diesel, and I do not think you will be looking for spark on that one!
For the 5.7L, the best suspects are the crankshaft position sensor and the camshaft position sensor. The Engine Computer needs the signals from them for spark and injector timing.
Wednesday, June 22nd, 2016 AT 10:43 PM