There are all kinds of things that might make your car vibrate, but the most common culprits are your tires or wheels. The good thing is that tires and wheels are both easy to check, and they are easy to fix or replace.
Diagnosing Tire Problems
1) Wheel Balancing
Does your car begin to shake when it reaches 45 mph or more? If so, the chances are you need to take your car to a tire professional to have your tires balanced.
Your tires are usually balanced when they are new, but that doesn’t guarantee that they stay balanced as their tread wears down. Tires become lighter as they wear down, and they often don’t wear evenly. For that reason they may need to be rebalanced.
If your tires were already recently balanced, check the rims to make sure one of the balance weights has not fallen off. If that has happened, you might be able to have your tires rebalanced for no charge.
2) Tread Separation
Does your car vibrate most strongly between 10 and 40 mph? Check for tread separation, or ask a tire professional to take a look.
Tires separate when they are exposed to excessive heat, often because they have been run underinflated for a long period. The tread begins to actually separate from the tire carcass.
You can check for this yourself by jacking up your car and spinning the tires while watching the tread patterns. If the tread pattern gets wavy in places instead of being completely straight, or if you see bulges, that’s an indication of tread separation.
If separation is the cause of your vehicle vibration, replace your tires immediately. Tread separation can be extremely dangerous when driving because it can result in a blowout.
3) Flat Spots
If your vehicle has been sitting for many days in the same place, especially when parked on hot asphalt with a heavy load, your tires are strong candidates for developing a flat spot. A flat spot can occur at the bottom of your tires where they press against the road. Generally, if you drive for a while at slow speed, your tires will become round once again.
4) Bent Rim
You might have bent a rim by banging into a curb too hard or driving too fast into a road hazard, such as a pothole. It is often difficult to determine a bent rim by yourself. If your car is vibrating and there is no obvious connection to other tire issues, have your tire specialist check for a bent rim.
4) Other Causes of Vibration
It’s a good idea to check your tires first because statistically, they are the most likely cause of vibration.
If your tires and wheels receive a clean bill of health from a tire shop, the next step might be a trip to your mechanic.
Your mechanic might find the vibration is generated from your engine, poor alignment, or worn or damaged brakes. Vibration might also come from a bent axle or driveshaft, or worn out velocity joints at the end of the drive axles, to name some of the most likely causes after tires and wheels are checked.