A few people suggested the thermostat. I don't think so. The thumping is the water in the radiator boiling. In my experience a stuck thermostat keeps the water in the engine, which gets hot. The water in the radiator stays cool, so it shouldn't boil. Maybe if I yank the thermostat I could drive her a little further before it gets too hot, but I think a tow is in my (near) future. Rob > >still thumping? Maybe and most likely a stuck thermostat replace it I use >Stant superstats. Best that I have found they cost about $2.00 more than a >standard one. _________________________________________________________________ Join the world�s largest e-mail service with MSN Hotmail. http://www.hotmail.com