My Brakes are Barking at Me

My new 2011 Prius seems to be making noise described on this thread on occasion when braked lightly. I also felt the brake lock up when first backing up out of a parking spot and when I pump the brakes when parked the car with squiggly lines appear.

Is this an issue that I should bring the car back to Toyota?

Got the Prius last month brand new and has less than 500 miles on it. I also notice that the Prius brake seems really dramatic and will give you a hard stop if not very carefully pushed.

 

I just came back from Lake Tahoe/ Stateline NV and was at 7600 ft elev, temperatures around 40-50 F, with very dry air. The brakes did make one short sea lion like 'bark' whenever I applied the brakes. There was no squealing or 'metal-on-metal' noises. Braking ability did not seem affected, and the '07 car has 98k on it, still with the original brakes. When I got back down to the Central Valley, the noise stopped.
Is fixing it just a matter of bleeding the brakes, or does it mean the actuator is going? I have noticed the car does not brake as good as it used to, or as good as the '09 I drive for work.
I assumed that was just worn pads, but the tire shop (America's Tire) refused to tell me if my brakes were worn when they had the wheels off last week. With so many miles on the car, it seems the pads should be soon due for a replacement.
My plan is replace the pads, bleed the brake lines, and see if that fixes it. Does anyone else have experience with fixing it? Or had the brakes fail? How long do the pads usually last?

 

Do not attempt to bleed the brakes unless you have both the Toyota techstream or equivalent equipment and the knowledge of it's use, also do not open bleed valves when changing pads. The Prius brake system has many valves that must be opened before bleeding can take place.

 

The "Bark" is just air bubbles passing through small apertures in the Gadget (expensive replacement) that simulates brake pressure. At high altitudes (low atmospheric pressure) bubbles can form in the hydraulic fluid and temporarily cause barking. If the bark goes away at lower altitude, just ignore the issue.

Bleeding the brakes (you need instrumentation to do it correctly) will fix a low altitude bark as long as the hydraulic system is secure and doesn't led air into the system.

JeffD

 

Well I'll be darned. I heard the clucking/barking when on a ski trip to Winter Park last week (9000 ft). Haven't heard it since I returned to Chicago. Go figure!

 

I LOVE THIS FORUM. My 2007 lives in San Jose CA. We're taking it cross country. Up in Flagstaff we noticed that the moment we pressed on the break pedal it sounded like car next to us was honking. The next day at Williams and the Grand Canyon it got worse and made a rather loud barking noise from behind the glove box every time the brake pedal was depressed. After reading about the possible altitude issues we decide not to take it in for emergency service or bleeding, and sure enough down in Sedona on a hot day the noise disappeared, but came back the next day in Santa Fe. We're now down in the plains the the noise has disappeared for good. Another data point for those who run into this in the future.