C43 Cruising Humming Noise

[mattc43]

Had the C43 for a couple of months now and i'm loving it but there is one minor thing which is niggling me.

When you drive along at a constant speed there is a humming/buzzing noise, maybe coming from the back of the car. The noise is only evident when you are on a very light throttle ie just enough to hold speed. If you lift off it goes away and if you accelerate, however gently, it also goes away.

The car drives absolutely perfectly. Gearbox is silky smooth, no vibrations, hesitations, car pulls really well and is generally great. Just this minor little thing which, if i could get rid of, would make the enjoyment even better.

Any ideas?

 

[Stratman]

The first thing I'd do is check the diff for leaks and correct fluid level.

 

[mattc43]

The first thing I'd do is check the diff for leaks and correct fluid level.

Thanks but the diff oil has been changed (got a full service done inc diff oil, transmission fluid etc) and all was good apparently. Fluid level was good and pretty clean by all accounts.

 

[mclinn]

loud whining sound when I travel up hill and now very load noise possibly from gear box - any ideas?