Loud grinding at low speed

ford
focus

#1

Hi everyone!

I was just pulling into a parking space approximately an hour from my home when the car starting making this really loud grinding noise and the brake pedal was very stiff. I thought it was my brakes grinding metal to metal. It was late at night and I couldn’t see anything, but didn’t want to drive it, so I Uber’d home and had it towed the next day to my mechanic.

I had absolutely no problems with the car before last night. No squealing, no vibrations, no lights coming on… nothing. I was not dragging anything caught underneath the car. I got on the ground and looked, twice.

My mechanic took everything apart and said everything looks fine. They drove it today 3 times and could not reproduce the problem. Is it a sensor or the ABS module malfunctioning and causing problems? I’m at a loss. I’ve had the car for just under 4 months and have 8 months left on my warranty.


#2

Year, make, model, mileage?
Maintenance history? Any recent repairs done?

Be sure you keep proper detailed records; I like to keep my copies of the shop orders. read your warranty carefully. Many don’t cover brake systems. Some cover mechanical problems. The devil is in the details.

As to the problem, My first guess would be an intermittently sticking caliper. But it cannot be diagnosed over the internet. However there are possible variables… if you live where it dropped well below zero yesterday and you have moisture in the system, the fluid may have iced up. If nothing else can be found and the failure cannot be verified, I’d as a minimum flush the brake system out with fresh fluid.

I commend you for doing exactly the right thing. Brake failures kill people, and it would not have been worth taking the risk. Getting home safely first and then worrying about the car shows excellent judgement.


#3

Oops, sorry, I thought it showed up on the thread. It’s a 2014 Ford Focus. I don’t remember the exact mileage, but it’s around 40k. I bought the car from Prestige Ford in Mount Dora, FL. Definitely wasn’t an ice thing. Thanks for replying so quickly!


#4

Is this vehicle still under warranty? If so, I hope you’re not taking it somewhere other than the dealer. You could invalidate your warranty for any problems related to any system that a non-dealer shop does work on.

Those are typical symptoms of a malfunctioning ABS system. Did the shop check for and ABS malfunction codes?

There are other possibilities too. Newer cars have stability control systems that work by applying whatever individual brake(s) it deems necessary to compensate for bad driving, but I confess to not being as versed in these as I should be. Did the shop consider a malfunctioning stability control system?

I wish I could be more help, but if I’ve stimulated the thought processes of others here I’ll feel like I’ve contributed something. If not, at least I’ll have tried.


#5

A friend of mine was looking it up on the internet and said he found people discussing the brake line going to the caliper was collapsing. Sound plausible?


#6

It is plausible. Brake lines are made in layers, an impregnated sheathing around a rubber hose basically, and the internal lining can become detached from the outer sheathing and collapse.

However, this is NOT a diagnosis! I’m simply answering the 'is it plausible" question. I would not expect this on a two year old vehicle unless a brake had been dragging and seriously overheated the caliper, damaging the flex line.

I return to my recommendation to keep after the dealer. With your owner’s manual you should have received a “kick it up the ladder” procedure for getting the manufacturer involved. Follow that, keep detailed records including your copies of the shop orders, and check out your state’s “lemon law” in case it can be used to your advantage.