Bumpy ride at various speeds

Here over the last week or so I’ve noticed my car start to have a bumpy ride around 35-42 ish mph, and around 65-70 ish mph. It feels worse probably around that 40 range, and seems to be even more pronounced during acceleration. It’s not a super high frequency or anything, maybe just a couple hundred HZ. I have been driving it considerably more over the last month with my new job (around 140 miles a day, mostly highway/interstate driving). I’ve got an oil change/ fluids checked about 3 weeks ago or so.

And your car is…model? Year?

Do you live within 50 miles of NYC? If so, it isn’t your car.

Ha sorry, forget to mention the make and model.

2000 buick regal ls.
And no, no NYC, a little southwest of there in Oklahoma.

Does it feel like the vibration is coming through the steering wheel, as it might if the problem was a front tire? Or is it more a seat-of-the-pants bumpiness?

Hmm I think seat of the pants bumpiness.

I’d start by having your tires checked and your wheels rebalanced at a tire shop. Maybe a wheel weight has fallen off. Tires can also wear unevenly due to worn struts and start to make a bumpy ride. Have your struts checked, too. When was the last time you had the struts replaced? If they’ve never been replaced, they’re probably due.

It could be you need new struts AND new tires, because if worn struts have let the tires get worn unevenly, new struts alone wont make the bumps go away.

Try the rebalancing first. If that doesn’t work, then you might need new struts and/or tires. But first use the “Mechanics Files” section of this site to find a reputable local mechanic to help you with diagnosis.

Got some new tires yesterday (they were in need anyway) and the problem still persists. What about the struts/suspension would make it much more bumpy when accelerating vs maintaining the speed?

Hmmm…wondering if it might be one of the front wheel drive axle/CV joints since you say it’s “much more bumpy” under acceleration. I’ve heard of those going bad and causing vibration/bumpiness, though I’ve never had a bad axle myself.

Problem is, there’s no way I’ve heard of to diagnose it for certain. People seem to end up replacing axles on a trial and error basis, and sometimes it solves the problem, sometimes not. Also, you have two separate drive axles up front, so it could be either one, or both.

Your best bet is to find a good mechanic who can drive it and know what a bad axle feels like, but not every mechanic is going to know.