Oscillating - Noise after accident (front left)

Question

I was recently and unfortunately involved in a road traffic collision with a concrete kurb (sidewalk) in my BMW 320d Coupe at approximately 45 mph as I was attempting to avoid another vehicle. I'm after a bit of general opinion here and I know it might be purely speculative.

As I said, the car has hit the kurb at a decent speed, it's suffered damage to the front left tyre, alloy and rear tyre and alloy wheel. All of which have been replaced under insurance. I've been told a 4 wheel alignment has been undertaken and everything is within "tolerance".

However, there is a noise coming from the front left wheel, a noise that hadn't been present prior the collision.

Specifically, the noise starts at about 50 mph, and continues to get louder with speed, this is accompanied by a vibration through the steering wheel and shaking through the body of the car. I'm 110% adamant that it was not present prior to the collision taking place, and it was the sole reason I decided to go through my insurance in the first place as I was just going to have the repair done myself which would have probably been cheaper in the long run.

After a week and a half of waiting, I had the car back and drove it home via the motorway, just after getting up to speed the noise is still very much present.

The noise is still present after dipping the clutch, and I cant feel any vibration through the gear stick (shifter).

The car was recovered back to the originating garage, and they called this afternoon stating no issue could be found (which) had been confirmed by two engineers.

Any thoughts?

Answer 1

If the sound gets louder and higher pitched the faster you go then that would suggest that your wheel bearings have been damaged. That might account for the vibration but I doubt it, more likely you have an unbalanced tire or some play in your suspension/steering linkages post-accident.

Replacing the front left bearings might clear up the noise and possibly the vibration, it would need to be tested at speed to see if the symptoms come back.

Personally I'd be concerned that your garage is telling you there's nothing wrong when there obviously is, and that they haven't checked on something this simple already. You might want to get a second opinion.

Answer 2

Just in case anyone comes across this in the future.

I was told repeatedly by the garage, the insurance company and an independent inspector that my car was "fine" and I was imagining things. What I would say is be persistant, it's your car and you'll know how it felt before the accident and after.

Ignoring the idependent inspectors decision I took the car to a BMW approved garage and paid for time with an engineer to go on a drive to demonstrate the issue. He immediately confirmed that it was the wheel bearings on the affected wheels just as I'd suggested from the start. I did this entirely at my own risk and out of my own pocket to prove a point.

BMW provided the evidence of the damage to my insurance and the repair work was paid for there and then, BMW also noted that the rear shocks we're damaged and we're subsiquently replaced in addition to the bearings.

Point is, if you know your car well and beleive there to be an issue it can be worth persisting and paying for an independent inspection that has no relation to the insurance company or the repair garage in question. Keep all copies of reciepts to keep as evidence.

Disclaimer. I was prepared to swallow the cost of this expense of the additional inspection, and was reimbursed by the insurance company of that cost. I can't guarantee that for your circumstances.

Though I don't believe it was related to the crash both front lower control arm bushings had also gone, I found this myself a few weeks after the crash when I had a weekend to get under the car. There was a decent amount of play in the control arms and I replaced with aftermarket bushings. I kind of expected that on a car that had done almost 100k miles and it made a massive difference to the handling.