Overheating at low RPM - thoughts?

Do the fan test above (with the newspaper and don’t go crazy on thickness). If you are losing coolant, you should probably use a dye and see where it’s going. If you can’t see it, it’s probably the head gasket.

 

Build date for the truck should be on the VIN sticker on the inside of your driver’s side door.

Assuming it’s the original motor.

If not, I think there’s a tag on the engine. Someone might be able to provide info.

Good luck!