Resonance Anyone

[hector46]

Does anyone notice a slight resonance on their diesel UC at motorway speeds in top gear? It's between 70-80mph which is where I tend to sit. It's more noticable on quiet surfaces, stops with engine coasting. Thought it may have been wheel imbalance but seems like either exhaust or possibly the drive system under load? I noticed the first time I drove on the motorway. As an experiment only I took the car above 85mph for a few hunderd metres and it dissapeared so appears to be at specific speeds.

[hector46]

Just to update my own post I've tried revving the engine to around 2000rpm static and no resonance. The other bit not mentioned before is it's most noticable on light loadings.