To my knowledge: approx 5 years ago the WP, Rad, and t stat was changed. Operated fine since then until about 6 months ago. Noticing the truck running hotter. Losing coolant. And what seemed like very small chunks of rubber in the coolant. Started over heating on me.... So, Just flushed and replaced the T stat the WP. Still overheating. My question is. How probable is it that the Rad has gotten clogged with what I'm guessing is the remnants of the old WP.. and how to i remedy it. engine gets hot. Top hose on rad gets hot. Bottom hose doesnt. Opening the drain on the Rad while engine is hot. Cold water drains out.