frequency

Hi. I get a high frequency vibration at highway speeds. This vibration comes and goes but is becoming more frequent. It generally comes on as I drive or after I turn off my cruise control and the truck seems to tighten up instantly with this vibration. Truck has 282k miles. All New rotors and...

I don't think this is the same issue others have posted about vibration at idle that indicates new plugs or a tune up, as it's more of a slight deep tone droning sound when I am driving (2004 LX470) but come to a full stop only, like at a stop light, but if I slightly add throttle while keeping...