smoke coming out of rear wheel after braking hard (very hard). wtf?

[pomidor]

...so what exactly is smoking here?

The scenario:

1:
Accelerate, then brake very hard (for a good amount of time).

2:
Repeat #1 about three times (back-to-back)

3:
Stop the car and observe for smoke


Rear (passenger side) wheel has smoke coming out of it (for about a minute or two).

I peeked in the wheel to see where it was coming from. It looked like the brakes.

There was quite a lot of the smoke

I did have the car oil-sprayed, but that was about a year ago.

Are the brakes heating up burning residue of that oil, or are brakes themselves overheating and smoking? Or something else? Do brakes smoke like that? Mind you, the other three wheels had no smoke coming out of them at all.

I'll keep a camera handy next time so that I can take a video, if needed.

 

[tngai]

did you have new pads in them? or someone serviced your breaks?
or your caliper is leaking oil?

 

[njaremka]

if the brakes are relatively new, its completely normal - it means the brakes are bedding in.

OR, if the brakes are older, it means they are cheap pads.

 

[pomidor]

Rear brakes are old.

If pads are cheap, why didn't the other (rear) wheel smoke too? Unless they have different pads. Since I bought the car, I did the front brakes only. I don't know what pads are in the back.

The smoke was coming out from behind the disk (inner side). If the caliper leaked brake fluid, it would spray it on that side. I checked my brake fluid level few weeks ago. It was full. I figured that there are no leaks, however, perhaps there is one now. I'll check the level again today, although if very little of it leaks out, I might not be able to notice.

 

[pomidor]

I checked the brake fluid level. It was a bit off, but not by much. Just a few millimeters. I'll keep an eye on the level though, periodically. Maybe leaking caliper is the culprit.

 

[mazdaspeedp]

maybe one of your calipers is seized