[Conant]

Good day,

M car is vibrating most violently from around 100km/hr and I don't know what the problem is. It gets worse at 120km an hour; sounds as if the wheels of the whole car are bouncing off the tarmac! The vibration can be felt throughout the whole car. Please help!

 

[EricSmit]

Either wheels out of balance or wheel bearings.

 

[ChevyGuy]

It could be a bad tire. I've had tires that have developed lumps that will cause vibration. You might be able to feel it if you run your hands over the tire. I'd suggest wearing gloves since if the steel belt is sticking out, it could be a painful discovery.

Assuming the car is out of B2B warranty, my suggestion is to take the car to a good tire place. By "good" someone who has the equipment to go beyond just changing tires.

 

[obermd]

Start by cleaning the tires and wheels. Snow and ice can cause this. Once that's done recheck. If you're still having this issue get your wheels rebalanced on a good spin balancer. If it's still occurs then check the tires. Once you've ruled out the wheels and tires then start looking at suspension components.