Fw: Truck overheating(no lbc) oponions needed

Hi Bryan,
Maybe the mud is from use of stop-leak gunk by the previous owner.
By all means remove and check the thermostat in a pan of water.
Look for coolent drips around the water pump end of the engine (when my
LBC parts chaser was losing coolent, there was almost no evidence on the
ground).
You'd better check for coolent in the oil (mayonnaise under the rocker
covers),
and a compression check. I'd be concerned about a blown head gasket :(

Jeff