I vote HG or eroded cooling passages in the head itself. Sure the engine was installed only 6K miles ago, but where was the engine sourced from? Warranty? Could have been a throw together in a hurry engine. As long as the short block is sound, even a cracked/eroded head is a cheap fix considering the price you paid on the truck.

Washington huh?......wunder how I missed this one?? <img src="/forums/images/graemlins/confused.gif" alt="" />

Keep eyes peeled for a 89'-95' extra-cab with blown motor please! <img src="/forums/images/graemlins/kewl.gif" alt="" />

~Darin <img src="/forums/images/graemlins/baby.gif" alt="" />