N.B.: I have already made an appointment with the mechanic and am dropping the car off tonight to get looked at. I am just curious about what this might be and how much it might conceivably cost.
I have a Toyota minivan. For the last week or two, every time I start the car and let off the foot brake, there’s a loud thump from the right rear. It sounds like maybe it’s coming from the wheel well. It also occasionally happens if we’ve been stopped in traffic for a while and then I take my foot off the brake. It is really a very loud thump, and the first time it happened I thought maybe something had run into the back end of my vehicle.
Possibly unrelated: For the past three days I have also noticed an odd odor in the van. I don’t recognize it but it smells vaguely mechanical in nature, i.e. like a smell you would notice in a repair shop or something. I know this is totally vague. For all I know, it’s a misplaced chicken Mcnugget slowly rotting in the back seat.
Opinions? The thunk + smell is wigging me out, so that’s why we have the appointment with the mechanic.
Without knowing whether you have rear drum or disc it sounds like the brakes. On a disc setup I would say your parking brake is sticking. Generally drum brakes utilize the same shoe for the parking brake as they do stopping, and could also be sticking due to a broken spring, grooved drum.On disc brakes it might be a grooved disc, as the parking brake shoes on disc brakes generally run on the inside of the brake disc or damaged hardware therein. A year or vin number may help to make a better guess, but a visit to a qualified mechanic sounds like the right move.
If you rarely back up then drum brakes don’t self adjust. I’ve had rear drum brakes loosen up to the point where they clunk. Easy way to eliminate this is as a problem is to back up and repeatedly pump the brakes. This activates the self adjusting part of the brakes.
Update. The rear drum brakes were leaking fluid to the point that the shoe was saturated, thus causing it to stick in place. Also, in an unrelated note, the front brake pads were apparently down to 2mm, which I guess is pretty low. Total damage: $600. Not rear-ending the guy in front of me when my brakes catastrophically fail: Priceless.
