To clarify-:D It does not matter if I am pulling a trailer or not it sounds like the RPM's are high. Im not lacking power, just sounds like I am running it at high RPM's. The fan talk makes me think--- it does sound like a airplane under my bonnet. So if the fan is not functioning correctly would it be making noise? It has had a recent tune up. New plugs and wires, cap and points. I also had the exhust manifold fixed. It was leaking. I can drive faster than 55 but just sounds high. I have two fans. One on the engine and a set of electric fans in front of the radiators. Again thanks. I have not went campong because I am afraid of it breaking down.