BigFuel· BANNED by Kris
I'm with Pogue and think HPOP sump isn't holding oil. Also with really cold temps the batteries are really stressed. The PCM needs to see ICP at 500# before allowing the engine to start. With the glowplugs running, super cold batteries, and cold oil you are straining your starting system while cranking. Best bet is to hook up a good heavy duty charger/jumper and try your cold start again. If the added power spins the truck faster and starts quicker then you are looking at new batteries (both) and possibly a new positive cable.