Accidentally drove with parking brakes on?

"I didn't realize they were up" ? "My brother saw it was up"?

You have a parking brake lever between the seats and have it applied while driving.

You know the damage because you smell it.

You operated it for 30 minutes at speeds above 40.

This means you need rear linings, but are the hard parts heat checked? the hydraulics damaged and leaking?

The axle seals leaking?

After you get a complete inspection, the estimate will tell you.

My question is, how old are you? and how did you get the keys to someone's car? Take it back to the home and put the keys back before someone notices it was missing.

Geo is correct. If the parking brake works, it's fine. Doesn't seem to work too well if you easily drove off with it on. If you have an automatic, and are not parked on a hill, you don't need to use the parking brake.

Check your brake fluid level, the brake light will come on if the fluid is low.

You added a lot of wear to your rear brake pads. They will therefore need replacing sooner than if you hadn't done this.

Make sure the park brake still works. If it does. you haven't killed them completely, just taken 6 months off their life.

BTW, get into the habit of briefly scanning your instrument panel every few minutes. Those little lights and gauges are there to help, and warn you of even more serious things, like loosing coolant or oil pressure, that WILL kill your car in minutes.

Depends what kind of park brake mechanism your car has. If it is a mechanical mechanism you will have worn a fair bit of material off the pad or shoe, it may need replacing or you might be lucky and get away with an adjustment. If it is electronic you may also be looking at park brake actuators.

I want to point out something. Parking brakes have a purpose, mainly for manual transmission cars. If you had put the parking brake on properly, the car wouldn't have moved. So you need to think about this, and learn how to use that parking brake.

To answer your question: Yes it's bad. Yes there will be some damage.

p.s. You thumbs down people are ignorant!

Mechanical rear brakes are not strictly for parking especially with an automatic transmission which has a park setting. They are primarily for emergency situations where your hydraulic brakes fail. Yours must have been already worn or out of adjustment since they didn't keep you from driving the car. I doubt you did any serious damage but you should at least have the E-brake adjusted so it does stop your car in case of an EMERGENCY!!!!!.

You fried the parking brakes. Brakes can be fixed. At a cost. An expensive lesson that you learned.

You probably did some damage if you drove that long with the brake on. I would get them checked soon.