Car shaking and nothing seems to fix it

October 14, 2024 5:15 PM

2016 Honda Fit, 4 new tires Sept 2022. 1 tire had a slow leak and needed to be replaced in summer 2024. Drive about 4000 miles a year, mostly city driving on not great roads.

Took car in 3 weeks ago for inspection and tire rotation. After this, car shook between 55-60MPH. Took it back to mechanic who rebalanced tires and said 1 rim is slightly bent, shaking still happening. After that was ghosted by mechanic. Took it to a tire shop, tires were not balanced, they rebalanced them and also fixed the bent rim. Now the shaking happens 60-65MPH. The wheel with the bent rim moved from the back right to the front right. Took it back to tire shop who put the car on the mount and they said the front tires are out of round and I need new tires. Doesn’t seem reasonable to me, especially since one of them was bought 3 months ago, but I don’t know, if they wanted to rip me off seems like they would have told me I needed new tires the first time I brought it to them.

What in the world is going on? I feel really stupid around cars and am at my wits end. I need this fixed!

posted by rhymedirective to Travel & Transportation (11 answers total)

I think first you need to figure out if your bent rim was adequately fixed. You may need a new wheel. Driving on a bent rim (the metal wheel) will absolutely screw up your tires (the rubber bit). I'd take it to a different shop and tell them to please check all the wheels. Have them show you the uneven tire wear. Then you can decide what to do.
posted by ananci at 6:15 PM on October 14

If you hit something hard enough to bend a rim you could easily have damaged other suspension components as well. This is how I know how much a new rack and pinion costs. Although my symptoms were very different from yours (a nasty grinding noise when I turned the steering wheel). A tire shop generally will not be able to diagnose problems elsewhere in the suspension; a good mechanic is needed for that. In my case the mechanic (the dealer!) that replaced the rack and pinion totally missed a bent rim that wasn’t found until I got new tires a few months later. So multiple people looking at it may unfortunately be needed. If you can find a mechanic who does a lot of suspension work I would have them look at it.
posted by TedW at 6:26 PM on October 14

Are you taking it to a tire shop and not a general mechanic? I had a shaking at speed after a tire change that certainly felt tire related, but turned out to be a problem with the control arm.
posted by Ardnamurchan at 6:27 PM on October 14

I took it to a mechanic who seemed to think the shaking was tire/wheel related. This mechanic then ghosted me. Thus the tire shop.
posted by rhymedirective at 6:40 PM on October 14

Is this the same tire shop where you bought the tires two years ago? If it isn't, I'd take it back there. If they say the tires are damaged in some way, ask for more detail about what specifically is wrong (because two year old tires shouldn't be out of round) and what has caused the problem. I'd also get them to check the bent and fixed rim. If this is the same tire shop, then you need to ask them why the tires you bought two years ago are out of round.

If the tire shop say everything is fine, then it's probably time for another mechanic who can check suspension and steering components for you.
posted by ssg at 7:19 PM on October 14

Lol I bought the tires 2 years ago from the mechanic that ghosted me. That’s a non-starter. I’m never going back there again.
posted by rhymedirective at 7:28 PM on October 14

I would recommend a two step approach.

Step 1: go to a good tire, wheel and alignment shop. Not a mechanic who does tires. A place with a good rep that lives and breathes wheels and tires and alignments. Share your concerns with them and ask that they do a road test to reproduce the issue.

A car with proper alignment and balanced tires in good repair may have vibration issues that are not caused by wheels and tires. This shop should be able to identify and fix the vibration or rule out wheel and tire problems. They may also be able to ID suspension issues. If they solve it, yay. If the issue is unresolved, bring their writeup to …

Step 2: go to independent shop that specializes in Hondas - the kind that does them all day every day and has seen every weird thing Hondas can manifest.

Tell them the problem, show them the diagnosis from the wheel and tire place, ask them to do a road test. At this point it's possibly transmission, suspension, or rotors. They should be able to ID what's up.
posted by zippy at 8:06 PM on October 14

I had an issue like this with an old car—after a tire replacement, the car would periodically shake at highway speeds. It turned out the new tire was either a bit smaller or a bit larger than the other ones, which was causing the issue, some kind of misalignment was occurring. Could your issue be something like that?
posted by miltthetank at 8:43 PM on October 14

I read your previous question about this issue, and as I read it there was nothing functionally wrong with your car and you took it in for routine tire rotation, but when you got it back, you had vibration at highway speed, one rim was mysteriously bent, and there was a "slapping" sound when driving over local roads.

I don’t see any other explanation for this other than that they did something to your car that caused these problems.

The most common serious mishap in rotating tires is that the car falls off the jacks when one or more tires aren’t in place, but it would require unusual circumstances for that to bend a rim. I suppose it could happen if one of the wheels was dismounted and lying flat on its side underneath where it was going to be mounted when the car fell, and the car fell on top of it and "bent" it, but that would result in a very unusual pattern of bending. Most damaged rims occur when a tire blows out or is already flat and hits an obstacle, and I would think that would be called a 'dent' most of the time.

I would say the slapping in the original question occurred when the wheel lost contact with the road— jumped up, essentially — and then slapped against the road when it came back down. That could be caused by a seriously out of round rim among other things including suspension problems.

You mentioned that they were having trouble getting a replacement rim: "The mechanic is looking for a used rim to replace it with but not having much luck, hence the wait". I don’t think it’s out of the question that they had another customer who needed a new Honda Fit rim, and they gave that person your rim and you ended up with their damaged one. Then the mechanic could charge them for your rim and get that car out of the shop, and then charge you for a new rim when one became available.

I would say you’re still having rim problems, because it’s unlikely for relatively new tires to be out of round unless the rims are. If both tires are indeed out of round, you might have two bad rims, and if that’s the case I’d say the scenario where the mechanic took parts from you car to repair another becomes dramatically more likely, and that the other car had a serious incident in which both front tires blew out when they hit something, both rims were damaged, they got your good rims and you ended up with their two bad ones.
posted by jamjam at 11:54 PM on October 14

I would say the slapping in the original question occurred when the wheel lost contact with the road— jumped up, essentially — and then slapped against the road when it came back down. That could be caused by a seriously out of round rim among other things including suspension problems.

This seems to track with the work the tire shop did to fix the rim, as the slapping sound no longer occurs. They seem trustworthy, and I watched them perform their tests, so I'm going to proceed with their diagnosis of front tire issues but before they install them, to say please take the car for a road test afterwards and what is the plan if the shaking is still occurring. My last ditch effort is to drive the car to a mechanic that my father uses and trusts, but it's an hour away, so I was trying to avoid that.
posted by rhymedirective at 6:39 AM on October 15

In almost 100% of cases, a shaking that only happens at a certain speed range (ie doesn't happen when driving slower or faster) is a balance issue, but could also be a not-round wheel or tyre. The fact that the speed range changed when the wheels were balanced is useful information, because it mostly confirms that the problem is in the wheels or tyres themselves, not in other components of the car. I have seen this happen with cheap and nasty tyres that are poorly manufactured to the extent they simply aren't round and cannot be balanced properly. So, don't assume that it can't be the tyres because they're fairly new. It's also possible that the bent rim has caused irreparably uneven wear on the tyre, so it's no longer perfectly round or that you had more than one bent wheel.

I'm inclined to believe the diagnosis that the tyres are out-of-round. Swapping the front and back wheels may cause a change in the nature of the vibration, which would confirm the diagnosis in my view. If you have a full-size spare, you could also swap that for one of the front wheels and see if anything changes.
posted by dg at 5:24 PM on October 17