Brake rotor rust unevenly to cause wheel out of balance

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It's a possible a rotor can rust in a manner that would cause wheels to feel like they were out of balance?

Or maybe for the rotor to get that bad it would be falling apart and not really usable anymore.

It's more of a curiosity question, could this happen?
 
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If you drive the car or truck for a while it will go away. When you hit the brakes there could very well be a pulsating feel on the pedal or steering wheel and it's perfectly normal. Brake rotors are very prone to rust and buildup when sitting for a short while especially if the vehicle sits outside. Car dealers will tell you it's normal and it happens all the time. My son bought a 2020 Jeep Cherokee Trailhawk that had only 2,000 miles on it and the vehicle shook terribly at first from brake rotor rust and accumulation. The salesman said it's perfectly normal and it would go away by the time we drove it 250 miles home. The salesman was correct.
 

JHZR2

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I’m pretty sure that @The Critic had emphasized ensuring that the hubs have but so much runout, and that the rotors are matched to minimize it, otherwise you get pulsation and wobble.

A running vibration would have me looking at many other things before rotor wear, but if a big bloom of rust for,s, anything is possible.
 
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I seriously doubt it. Secondly, the diameter of the rotor is too small to cause a major vibration due to imbalance.
 
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The salesman said it's perfectly normal and it would go away by the time we drove it 250 miles home.
Everything is better for the salesman once the customer is 250 miles away.

If there is heavy rusting while parked, on the first drive the rust may eat into the brake pad instead of the other way around. This leads to a persistent ring of rust on the rotor where the pad no longer touches, which reduces stopping performance. But it always seems to be symmetric, so it doesn't cause any shaking whether braking or not.
 
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The rotor has build-up that wobbles the pucks.

A handful of heavy stops from high speed might help. I've experienced this a few times over the years.
 
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Everything is better for the salesman once the customer is 250 miles away.

If there is heavy rusting while parked, on the first drive the rust may eat into the brake pad instead of the other way around. This leads to a persistent ring of rust on the rotor where the pad no longer touches, which reduces stopping performance. But it always seems to be symmetric, so it doesn't cause any shaking whether braking or not.
In this case the vehicle was not even a year old and was a 2020 Jeep Cherokee Trailhawk with only 2,000 actual miles. The dealership had 6 of these Jeeps and we drove 5 of them. All of the Jeep Cherokee Trailhawks had the vibration when braking due to sitting on the lot on a early Covid crisis. Sales were extremly slow and my son bought the Jeep 2 years ago for less than $20,000.00! Now 2 years later the same Jeep is $28,000. The vibration was definitely caused from sitting on the lot for 2 or 3 weeks without being driven. The gas tanks were all on empty and this is how many dealerships run their businesses. They cannot test drive vehicles every week and thus you obtain rust on the rotors. I would not call it heavy rusting. Rotors will rust after 1 rain and be rusty the next day if sitting outside.
 
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If there is rust on the wheel mounting surface it can happen. I had vibration. The wheels were checked for balance and they were all fine. However, after they were put back the vibration was not there anymore.

There must have been debris or rust on the wheel mounting surface. I had just rotated the tires prior to getting the vibration.
 
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I have found that old rotors can throw the wheel balance off. It wasn’t the rust in my case. It was uneven pad distribution resulting in uneven rotor wear. AKA “warped”. Mostly felt while breaking. But also felt in the steering wheel. Disappears with a new set of rotors
 

Donald

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I have found that old rotors can throw the wheel balance off. It wasn’t the rust in my case. It was uneven pad distribution resulting in uneven rotor wear. AKA “warped”. Mostly felt while breaking. But also felt in the steering wheel. Disappears with a new set of rotors
But that typically shows up only while braking. I have some minor wheel vibration around 60 mph.just plain driving.
 
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If you inspect the inside of the rotor, you can see it’s factory balanced. So if you’re shaking when you apply the brakes, chances are the rotor is worn down unevenly. So it’s not balanced. And will mimic a wheel out of balance when it’s turning. Rotors are cheap. I just put AC Delco rotors on my Nissan for $22 each. I replace the rotor every other pad set.
 
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I always like to give my cheap rotors a good drop on the cement of some hammering with a 3 lb to shake off that rust. My OE Brembo rotors at 135k miles are still rust free and usable.
 
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