Mazda MX5 - Rumbling noise and vibration - tangent

I bought my 2005 Mazda MX5 Mk3 2.0 litre sport from a main dealer last April. It has developed a rumbling noise and the steering wheel vibrates when at 40-60 mph. The edge of the doors have also started to rust. Advice please.

Mazda MX5 - Rumbling noise and vibration - Jon P

Assuming the rumbling noise is coming from one corner of the car, it is most likely to be a worn wheel bearing.

Provided your tyres are at the correct pressures, the vibration you feel through the steering wheel is probably caused by a wheel being out of balance - you may have lost a wheel weight - check the fronts first.