Metal Scraping Noise from front right?

[Yuzhou]

2012 Hyundai Santa Fe with around 56,000 km. I bought the car used 1.5 years ago. Replaced all brake pads and rotors myself about 4 months ago, and driven around with absolutely no problems.

Recently I’ve left it parked and drive it only once or twice a week on Saturdays and Sundays. Being in Canada, it’s getting cold and there’s been some rain this week.

So today (Saturday) I drove it the first time in 5 days, and after about 600 meters of driving I could hear an unusual whirring/howling noise. It was quiet but noticeable.
Drove 500 meters more and the noise turned into a metal on metal scraping noise, with varying frequencies. Sometimes a little louder and harsher, and sometimes back to the gentle whirring. Sometimes I could feel a very small vibration in my feet from the pedals.
Immediately stopped, checked around the car. Nothing wrong. Noticed noise only occurs when in motion, when stopped there was no noise. Occurs on the front right passenger side.

Drove about 1 km more, went up to 70 – 80 km/h, noise was there intermittently at the start but then eventually gone. In the rest of my 8 km trip, the noise was gone. Back to normal.

Could it be just some rust? Or should I get it checked out by a mechanic?

Topic

[none]

Since you have the ability to change you own brakes, don’t be shy to take the wheel off and have a look for yourself. I think there’s a good chance you’ll find the root problem with a good visual inspection.

Get the car safely lifted and the right front wheel off. The first thing you want to look for is a shiny score mark anywhere on the rotor, caliper, the caliper bracket, and even on the inside of the wheel. Look the brake slides to have shifted on the brackets. Look for any shims on the back of the pads to be falling off or have slid off partially. Check that the dust shield didn’t get bent to the point that it’s rubbing against the rotor.

One last thing to consider is that humidity or a lot of rain can play hell with drums and rotors sometimes in that it’ll likewise create bad noises until the brakes are applied a couple times and the surfaces are heated up. One other notable symptom of humidity/water affected brakes is that they’ll be absurdly, if not dangerously, grabby the first few times you use them.

[EricTheCarGuy]

It does sound like what’s called ‘flash rust’. It’s a film of rust that develops on brake rotors after a rain or high humidity situation. The other stipulation is that the vehicle sits for a period of time in this high moisture environment. I write about the issue here.

http://www.ericthecarguy.com/faq/solving-brake-problems

It should go away after a few brake applications at speed. Sometimes, if it gets bad enough, it can actually develop into a brake pulsation. In that case, having the rotors machined should solve the problem.

Please keep us updated on what you find.

[Author]

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