I've noticed now that the weather is turning colder my truck cranks for 45 - 60 seconds before it will fire and run. Once its running its fine, just cranks for a while while when cold. Any ideas where to start looking?

 

Plugs? Cap? Rotor?

Those could be needing checked, changed if it's been several years. Carbon is the enemy inside the cap and it only creates higher resistance when the rotor is trying to create electrical charge to send through the plug wires, and thus if the gap is to much in the plugs, it just adds to the problem.