hi i have vibration cannot figure out where its comming from you can hear it first at about 40mph once you get to 60mph you can feel it through the steering and seats after 70 it shakes the car to bits been told it may be the rubber coupling for the prop but dont know what to look for to check this i thought it might of been the centre prop bearing but this was changed and made no difference its not wheel balancing or wheels as i have had 3 different sets of wheels and tyres and made no difference thanks for any replys ivan

 

Hi There! I got 3 guesses… First, it sound more like a warped or unbalanced wheel & tires if the vibration can be felt throughout the steering column at certain speed. You said you have 3 set of wheels & tires and perhaps there is always a good one, but what if you regularly drive in a rough (potholed) terrain and inflict damage to all 3. My second guess is the prop shaft, yes, the flex disk or the rubber coupling they called it, aside from the center bearings and rubber mounts, it must’ve been worn-out or out of shape. I once saw a picture of a rubber coupling that looks like it has been fiber shredded because the owner use it frequently for drag racing. My third guess is the engine mounts or the small shock absorber like vibration dampers bolted on the engine to the chassis, with these problem some strong vibration are more likely to be felt during idling. Those three guesses are based on my experience, but other problems can also be attributed to axle wheel bearing or engine balance shaft failures, etc., etc…