Car vibration past 40mph

spl51285 · Post by **spl51285** » 20 Aug 2020, 20:16

My 2007 Volvo Xc90 3.2 FWD started having a bad vibration when driving past 40mph. It vibrates on acceleration but also while coasting in neutral. Vibrations a pretty much the same until it reaches 80mph and it get worst. I think it is localized on the left driver side.

So far i changed the following: front suspension struts, bellow, tower mounts with bearing plate, sway bar links, control arm with bushing, ball joints on both sides. On the rear i replaced the shocks and sway bar links. After this vibration was still there so i replaced the front left driver side cv axle and hub with bearing. I swapped the front tire with the spare to make sure that it is not the tire or balancing problem. (2-3 years ago i swapped the right passenger side bearing with hub and aftermarket new cv axle)

Still have the vibration issue. I've run out of ideas on that it can be or what else needs to be checked. Im thinking next to replace the motor mounts. Car has about 178K miles on it.

Post by **RickHaleParker** » 21 Aug 2020, 00:15

How old are the tires? Are they a matched set? Take a good look at all four tires. Sometimes it is shifted / broken belts. Uneven tread-wear will cause vibration.

spl51285 · Post by **spl51285** » 21 Aug 2020, 07:36

The tires are a matched set, but they all old. I have only replaced the front left tire with the spare to see if the vibration goes away. i will have to see if i change tires around if the vibration changes location i guess. I understand that uneven tire wear can cause minor vibrations but i do not see how it can cause something like this.

Post by **RickHaleParker** » 22 Aug 2020, 20:49

When you jack the tire off the ground.
1. Grab top and bottom of tire and shake.
2. Grab both sides and shake.
3. Put crowbar under tire and bounce up.

Any slack / play?

spl51285 · Post by **spl51285** » 23 Aug 2020, 19:00

So i went and followed the advice of RickHaleParker today. Even though i thought that the vibration was coming from front left and there it was felt the strongest, I went for a test drive with my wife driving while i rode in the left back seat and i still believed that you felt the vibrations worst in the front left. I rechecked all of the wheels for play top and bottom and side to side shake. All was well. I began spinning the wheels to check for bearing noise and i observed the back left tire with a bulge on the inside.
I guess lesson learned, don't only check where you think the problem is and check all potential sources of the problem.
Replaced the rear left tire with the spare and no more vibrations.
Thank you Rick for your advice.

Post by **RickHaleParker** » 23 Aug 2020, 20:09

spl51285 wrote: ↑23 Aug 2020, 19:00 I began spinning the wheels to check for bearing noise and i observed the back left tire with a bulge on the inside.

Good thing you found it. That was a blowout waiting to happen.

Did you run over a curb, pot hole or something other that impacted the tire?
Think back a ways, the damage starts off small then spreads over time.

spl51285 · Post by **spl51285** » 23 Aug 2020, 20:55

Its the wife's car. She claims that she didn't hit anything. I have my doubts, but know better than to argue about it.

Tires are old so probably will get them changed soon. Discount tire is supposed to have a sale tomorrow.

Post by **RickHaleParker** » 23 Aug 2020, 21:32

spl51285 wrote: ↑23 Aug 2020, 20:55 I have my doubts, but know better than to argue about it.

Best not to argue or accuse. It could of been a manufacturing defect.