Peterbilt is cranking but not starting in the cold?

i would say your fuel as gelled...bad newsPeterbilt is cranking but not starting in the cold?
Check the filters. If you are going to have the fuel gel it will usually be in the filters. Try the drains on them to see if you get fuel out. Most stores will sell a diesel additive for after it gels, a popular one is from a company called diesel performance, it comes in an orange bottle and says 911 on it. You dump some in the filters and the rest in the tank then cross your fingers.Peterbilt is cranking but not starting in the cold?
If you don't have a block heater you'll need to give it a shot of starting fluid to get it to start.Peterbilt is cranking but not starting in the cold?
If it's spinning other then the fuel jelling might want to check if the glow plugs are working.

Compression alone won't start it cold, it has to have the glow plug's heat to fire the fuel.