Low Pitch Hum from engine

[darcia]

While driving down the road in our 2004 MiniWinnie, powered by a Ford V10, we occasionally hear a low pitched hum that sounds like it is from the engine. It seems to come and go relation to nothing, not up hill or down hill or passing or ...................Does anyone know what this might be, it doesn't seem to be an outside wind factor. Thank you

[lllkrob]

A/C compressor cycling on and off?? Thermostatic engine cooling fan cycling in and out??

[dstinch]

Hello. I have a diesel ford van and i get the same thing. I think it is coming from the air intake (air cleaner) it does bother me at times but then it goes away. Go figure! Don