[jpstewart]

Can I get some input from some of you who know car stuff?

Short version:
How likely is it to damage a wheel bearing while doing an alignment?

Long version:
Nearly three years ago I had new tires put on my car, and had the (reputable) tire shop do an alignment at the same time.  On the way home from the tire shop, I immediately noticed the car was a lot noisier than before.  My first thought was "they broke something".  But I couldn't readily identify the new sound, so I talked myself into believing it must be tire noise and lived with it.

Recently the car got even noisier, to the point that it was impossible to carry on a conversation at highway speed.  Even driving around town the noise was unpleasant, to say the least.  And it was causing things to rattle rather loudly.  It was quite obviously coming from the right front wheel.  I speculated that it was a wheel bearing and made an appointment to have it repaired at a trusted mechanic.  (Not at the tire shop from before.)  I didn't tell them what I thought it was, just that an odd sound was coming from the right front wheel.  They, too, speculated over the phone that it was a wheel bearing and later confirmed that by taking it for a test drive themselves.  They replaced the bearing at a ridiculously expensive price.

I got the car back from them, and lo and behold the supposed "tire noise" I've had since October of 2018 was gone, too!  Not just the recent extra-loud worn out bearing sound, but the constant drone was gone.  So, obviously, the bearing has been bad since the tire change/alignment.  It was never tire noise.

I suppose it is entirely possible that it is just a coincidence that the bearing failed on the exact day the tire shop worked on it.  But I'm skeptical, to say the least.  I doubt that mounting the new tires would damage a bearing since most of the work is done with the wheel off the car.  But I don't know what's involved in aligning the wheels.  So, in your opinion(s), how likely is it to damage a bearing while doing the alignment?  Or is it totally impossible to do that kind of damage during the procedure?

It doesn't really matter.  After all this time, no matter how likely it may have been, it would be impossible to prove the tire shop was at fault.  But I may want to avoid that tire shop in the future.

[Raion]

Usually the wheels come off for an alignment, so they would have had to remove those. whether it removed anything else is not necessarily possible. It's possible they beat on your axle nut or something, but that's not necessary for an alignment.

Either way, it's a three year difference, and anything could have happened in that time span.

[jpstewart]

Thanks for weighing in with an opinion.  I realize that since it has been nearly three years I'll never know exactly what happened or when.

What I know for sure is that there was a lot of wheel noise after getting the new tires that went away when the bearing was replaced.  So it wasn't tire noise like I thought for all that time;  it was early signs of bearing failure that I didn't recognize as such.  In hindsight, it's actually surprising how much driving I did on a worn bearing without realizing it and without disaster striking. 

Oh well.  What's done is done.  I'll try to let it go and not second myself too much.

[Raion]

Also, fwiw, I worked in a mechanic shop. We do make mistakes, often times not on purpose, and I'd argue, not negligently. A lot of cars are shittily designed and have parts that easily break. A good mechanic will be up front and depending on the nature of the failure, split the cost. A great mechanic will replace it on his own dime without saying anything. A terrible one will stick you with the bill or when something breaks, blame you.

[jpstewart]

I totally agree with that.

Based on your opinion and a couple of others I've gotten elsewhere, it looks like the probability of the tire shop having damaged something during the alignment is somewhere between "highly unlikely" and "nearly impossible".  So I won't hold it against them.  Which is good, because they're an otherwise great tire shop.  Even if they had accidentally damaged something, I've come to realize that the tire shop had no way of knowing.  They only drove the car into the work bay and back out into the parking lot.  They'd never have gotten up enough speed to hear the sound.  So they wouldn't have known if the sound was there before, after, or both.

(Earlier this spring I had a flat tire due to a screw through the tread.  They fixed it, in under 45 minutes, with no appointment, during a Covid lockdown, during their busy time swapping people over from winter to summer tires.  Total cost:  $0.  I think it was because they sold me the tires so they're covered by a "road hazard warranty".  Shop manager left his office to do the repair himself and insisted "no charge".  I like this tire shop!)

[flatlander_48]

@jpstewart You didn't mention what car you own, but one thing you might do (out of curiosity) is visit a form for people who own that make and model. If there is a somewhat common failure (but not enough for a recall), it might be a topic of discussion on the forum. That said, wheel bearings at pretty straightforward technology and it seems unlikely that removing and reinstalling a wheel would cause something untoward...