Truck wont start.

Intermidtent problems are difficult for the unexperienced mechanic. Having the proper diagnostic equiptment and qualified seasoned ASE certified technicians makes this type or diagnosis more normal than not. This is generely a same day repair once the diagnosis is completed. We would be glad to help 858-560-9131

If you don't have a GM specialist, find one. These things are not hard to figure for an experienced specialist. You haven't told me enough info for me to even guess. Check fuel pressure and ignition. If you want to find a specialist, here's a directory link for you: https://repairpal.com/gmc-repair-in-lemon-grove-california

Intermidtent problems are difficult for the unexperienced mechanic. Having the proper diagnostic equiptment and qualified seasoned ASE certified technicians makes this type or diagnosis more normal than not. This is generely a same day repair once the diagnosis is completed. We would be glad to help 858-560-9131

More information would be helpful. When it doesn't start does it just click, or does it crank over and just not start? It will probably be best to take into a shop and have it checked out to find the problem quickly. The more information you have for them will help reduce the time it will take to diagnose the problem.