Flash rust was my thought too, but why only RR?
thestumbler, Do you routinely use the parking brake? If so, maybe the shoes are continue to make contact with the drum for a few seconds.
In the old days we manually adjusted drum brakes just to the point of making a whoosh-woosh sound.
Wow, a lot of remarks since I last logged in!
I use the parking brake regularly.
The tires are reasonably new (within the last 6 months). But it’s no big deal to have them rotated, just to be sure.
Yesterday I tried to listen closely when I started off in the morning. It was early, and the parking garage was quiet. I drove very slowly and took a circuitous route. I heard the noise in the beginning as described before. Several times I stopped and started again (just the car, not the engine), and I’d say the noise happened maybe 3 of 6 starts, and then it disappeared entirely. This observation contradicts my 10 seconds from before, although each time I heard the noise it only lasted for 10 seconds (or less). But by stopping / starting a few times, I was able to recreate the noise for about 1 or 2 minutes.
As for ABS, I think that’s off the table. The sound happens only once I start moving. Wouldn’t an ABS self-test happen when the engine starts?
Suppose it is wheel bearings starting to go, but it’s too soon for the mechanic to be able to confirm. My car has about 52K miles. Would it be a waste to just preemptively replace all the bearings just for peace of mind? Being an electrical not mechanical engineer, I have no instinct how long wheel bearings should last.
This is the car in question. Not sure why they didn’t offer it in other markets. I find it to be a good fit for my needs, but then again, as an engineer, I have no sense of style. Maybe it’s too ugly for the North American market. If you search on Wikipedia, there is mention of a Kia Ray EV, but I’m not sure if that was anything more than a concept car. And to my knowledge, that is NOT available in South Korea.
The car in the photo that @texases posted sports the new harebrained logo, which looks like KN at first glance, not KIA.
They are usually pretty long lasting, but if they get dunked, under-water driven through in a flooded road, etc, , their demise can be much sooner, on the order of a few months. Driving fast over deep potholes can damage them sometimes too. A faulty wheel bearing usually sounds differently when turning vs going straight.
BTW, I’m curious why the parking brake on this car is a drum brake, when the main brakes are discs. It seems like a good thing, as far as having redundant braking systems. But in older cars with only drum brakes, wasn’t the parking brake the same as the main brake, but using a different method of engagement (cable vs hydraulic)?
Newer cars – forbetter braking — mostly use disc brakes on all four wheels. The designers needed to come up with a different type of parking brake. Disc-compatible parking brakes fall into two camps. The first type, the brake pads themselves lock onto the disc when the parking brake is used. The second type, apparently the type you have, the parking-brake discs also have a drum, and associated brake shoes on the backing plate, used just for the parking brake.
As @Mustangman said many many posts ago (and others agreed) - my money is on the surface rust. Rotors & drums rust up very quickly, and with the reasonably tight tolerances it doesn’t take much to create a little bit of rubbing when your first get going after a long-ish sit.
You’ve had it checked out with no red flags. And have no other symptoms (presumably). So I’d say to forget about it. Or if you like, maybe some of your “mechanisms” (whether something like caliper pins or cable actuated p-brake levers) are slightly sticky leaving things a little too tight. You could ask as shop to clean and lube all of that.
But mostly I’m sure you’re fine. By the description, the odds that this is something worse like a bad wheel bearing are almost nil. This isn’t how bad bearings present. But on the off chance that it is something like that, some manner of far less short-lived/occasional noise will show up in time.
I’ve had wheel bearings last hundreds of thousands of miles and also had one go out in 20,000. With go kart wheels though, hard to say.
With all of the ABS self-tests which I have experienced, the self-test takes place after a cold start, but only when the vehicle begins moving. The ones that I have experienced took place while moving at slow speed, during the first 50 feet (or so) of movement.
However, that’s not to say that this is the same functioning that your Kia has.
I’m gonna call this one solved. The notion of surface rust fits the symptoms the best. Regardless, I’m sensitive to the sound now so if it gets worse I’ll notice it and get it checked further.
I’ve always wondered why the wheel on so many car (and even truck) models here are so much smaller than back in the US, even for othewise similar sized cars.
I’m not sure where you are located, but presume outside USA. My guess is the reason the wheels are a bigger diameter in the USA vs there is b/c bigger wheels make the car sell better in the US Market. Buyers here are likely less concerned with the associated tire costs.
For crying out loud George !! He put his name and location in the original post .
It is a small vehicle, 2 feet shorter in length than your Corolla. Small wheel wells allow for more interior space.
