Vibration at 65mph

I have an 02 Saturn LW300 with ~88,000 miles. It recently developed a substantial vibration at around 65mph (+/- 2mph). This happeden within a week of having the tires rotated and balanced. I took it in yesterday and had them recheck the balance. They said that one of the tires had been out of balance and they fixed it. On the way back to work, traffic was such that I couldn’t get up to 65mph. This morning, the vibration was back and as severe as yesterday. What are the other possible causes?

Unevenly worn tires. A bad tire. A bent wheel. Improper alignment.

How many miles on the tires? How’s the wheel alignment?

There might be 25-30k on the tires. I’d have to check my records. I don’t feel it pulling to one side or the other, but haven’t had the alignment checked since the initial installation of the tires. It was the tire shop that installed the tires new that did the recent rotation and balancing. I would like to think that they would mention uneven wear. Haven’t hit anything to have bent a rim.

Is this only related to speed - or does it change at all depending on whether or not you are accelerating, just maintaining, or decelerating?

Is there any noise? Howling/humming/droning?

Did you have anyone at this shop drive it? Do they do road force balancing?

There is a very minor vibration below 65 but becomes very pronounced approaching 65 lessens by 70 gets bad again ~75. It’s a rather sudden onset and will continue if I maintain 65 mph. It does get worse from say 60 to 65 and 70 to 75, so yes it does get worse with acceleration. I don’t feel it in the steering wheel as much as in the body of the vehicle itself.

The only humming I have heard recently has been associated with turning at low speed, right or left. This doesn’t happen every time. I can have it happen with every turn the first time I drive the car for about 10 miles. I stop to drop off the kids and head to work and it doesn’t happen again. Have no idea if there is any relationship or not. But this happened prior to the tire rotation and vibration issue. I don’t hear any unusual noises when the vibration starts.

I didn’t have the shop drive it. I had hoped that the out of balance tire was the issue. I didn’t have time to take it back to them today. I think all they do is spin balance.

I’m very unsure about your shop. I think the tires are sound but there is clearly something else going on.
You might have a sticking front brake caliper. You would hear a noise at low RPM’s and feel vibration at higher speeds.

I agree it’s not tires. The change on acceleration is the clue. Tires wouldn’t change.

Rear wheel bearing?

I’m still not clear on whether or not it gets worse on acceleration. The question isn’t, is is worse at 70 that 60. The question is, if you are tooling along at 65mph and you stomp on the accelerator, does the acceleration itself change it? Or, alternatively, you’re tooling along at 65mph and then completely take your foot off the accelerator going to coast. Does that change it?

If the act of accelerating and decelerating changes the vibration then I would suggest having the engine & transmission mounts and the CV joints inspected.

If the vibration is mostly unchanged regardless of what you do with the accelerator then I would continue to worry about something at the wheels.

It does get worse as you hit the gas. It doesn’t stop as you are coasting, until you drop below 60-65 mph, but the severity of the vibration does lessen. It definitely does not remain unchanged with accelerating.

Thanks for the tips. I will have the CV joints and mounts inspected. My husband wants me to have them put the tires back where they were prior to rotation to see if the problem is still there. He doesn’t like the coincidence that I didn’t have a problem until the tires were rotated.