I have a 2010 Ford fusion with disk brakes all around. Recently I noticed at seemingly random times, it sounds and feels like the brakes on my rear left tire drag, almost as if the caliper piston doesn't retract back in fully. It's not all the time but seems to start after applying the brakes for several stops and if I apply them a little harder (like when a car in front of me slows down quickly).

After this behavior starts and I slow to a stop, I can hear the brake creaking. If I let off the brake pedal slightly to inch forward I hear it too. It also seems like when enough time passes before I go out driving somewhere again, the brake piston retracts in fully and the problem goes away for the time being.

Like I said it's not always but at random times. The wheel radiates heat when this happens (held my hand near it) while the other rear tire doesn't; so it generates quite a bit of heat.

It's winter with lots of snow and road salt. Could the piston be gunked up and therefore not retracting in fully?

Any ideas why this would happen? Looking for feedback before paying a $100 deductible to have my car looked at under my warranty service plan.

Thanks all!

Sent from my LG-LS980 using Ford OC mobile app

Unfortunately, there are a number of things it could be.

1. Worn pads.

2. Bent guide pin.

3. Failing flexi-hoses.

4. Failing piston.

If you know your way around a bag of spanners, you should have no trouble ruling out the first three possibilities.

Check that the brake pads are not worn down low, AND that the wear is even. If they're 'wedged' (thicker at one end than the other) then that to me would indicate that the caliper is sticking at one end, and I'd be straight onto checking out the guide pins.

To check the guide pins you need to remove the caliper, and pull the guide pins out. Put it in a drill at low-speed and spin it - any bend in the pin, however slight, will then become obvious.

The flexies can deteriorate on the inside and prevent fluid going back up to the master cylinder. Pump the brake a few times, then put a piece of hose over the bleed valve on the caliper and into a container, and release the bleed valve. If fluid squirts out then that indicates that it's still under pressure (when it shouldn't be). You can then get the flexi hose replaced.

I don't know of any way of testing the piston itself, other than eliminating all other possibilities, then replacing the caliper. Hopefully it won't come to that, though, as all the other options are cheaper.

Some good ideas for me to check out. Thanks!

Sent from my LG-LS980 using Ford OC mobile app