Drove ~600 miles with a failed brake booster. Found out via internet that Mazda had provided an extended warranty to cover this defect. When the dealership where I took the car tried to find the part it was on backorder with Mazda. The Mazda service manager at preston Mazda, john rosensteel, had one of his people drive to butler, pa from boardman, oh to pick up the part. I took the car to the dealer on the day before thanksgiving and the car was ready to go with a new boost unit by Friday. This was all due to the efforts of an excellent service manager at the dealership. Mazda failed me as a customer by not having the brake booster in stock even though it was the subject of multiple failures and an extended warranty.

- Greer, SC, USA

While braking normally for a stop sign, the brakes became hard to press and did not stop the car as normal. Hissing from the pedal area was heard and the car finally stopped halfway through an intersection after nearly standing on the brakes.

- Greenville, SC, USA

Brakes felt hard/stiff and vehicle didn't stop as expected. Almost hit another car. Had to apply brakes multiple times to slow down.

- Flower Mound, TX, USA

Loss of brake fluid; brake pedal hard to push. Unable to stop car; hissing noise at brake pedal.

- Beaufort, SC, USA

The contact owns a 2012 Mazda Cx-9. while driving 20 mph, there was a loud metal to metal noise coming from the rear of the vehicle. In addition, the gears failed to shift correctly and the oil and engine indicators illuminated. The dealer diagnosed that the brakes needed to be changed. The brakes were replaced, but the failure recurred and worsened. The contact also smelled fuel coming from the vehicle and the vehicle had trouble accelerating. The manufacturer was notified. The failure mileage was 33,000.

- Stow, OH, USA

At 44,000 miles, brakes feel hard and vehicle brakes slower than it should was nearly in an accident due to this. It took a much longer distance to stop. Emergency repair at local shop indicated brake booster failed. Really dangerous situation. Mazda should recall

- Phillipsburg, NJ, USA

Brake pedal became spongy and stopping power diminished considerably. Heard a loud hissing sound from the front driver's side. Had to fully depress the brake pedal to stop quickly.

- Northfield, OH, USA

Brake booster - when depressing the brakes (any time of day) there was a strange hissing noise, like air being released from a balloon. If the pedal was pressed closer to the floor there was a high pitched squeal. Brakes became very hard to press and the car became extremely difficult to stop. Luckily there were no card in front of me. A repair shop instructed me to check brake fluid (which was slightly low, and I filled it). This did not solve the problem. Brakes are even harder to press. From research I see that Mazda has had this problem for some years now. They should recall these cars and replace the boosters before someone is killed. We have four kids in our house and this is our only transportation. The car is no longer under warranty so I will be left replacing this on my own.

- Fleming Island, FL, USA

Breaks slowly strted to get harfer to press, here and there and last Friday went to take NY kids to the store and a couple neighborhood kids taged along when I got to the intersection my break pedal would not press down so thankfully no cars were coming as I slow rolled through the stop sign on a very busy fast speed higway. Called Mazda and they said they have had issues. Please if U notice any break issues get them fixed right away this story could have ended much diffrently with the loss of 5 kids killed because this is not a recall just a common complaint at this point it was under investagation at one point. Mazda needs to step up and send letters to owners of this issue.let me note Mazda was qiuck to get it N and fixed and gave me a rental. Thank U for that but all I can think about is how all this could have ended.

- Jay, FL, USA

The brake pedal on the Mazda Cx-9 became very very hard to push. Also, while I was stopped completely with the brake all the way down, the brake would temporarily release itself and I had to use two feet on the pedal to get the car to completely stop! this should warrant a complete recall as I almost drive into busy intersections twice so far!

- Orland Hills, IL, USA

Brake booster - I had issues pressing on my brakes, like a book had been placed underneath preventing me from fully applying pressure to stop my vehicle. This happened when I would back out of the driveway, go down the highway, and in traffic as I sat on the highway. When my car was stationary, I would apply pressure to the brakes and could hear a very loud hissing sound as though someone was letting air out of my tires. Luckily I wasn't in an accident, however, it almost happened on a few occasions. When I called Mazda to have my car checked out, I was told this is a common problem that seems to happen with the Cx-9 and I was advised to bring my car in.

- San Antonio, TX, USA

Brakes became stiff and difficult to press. When brake pedal pressed to the floor, loud squealing noise heard from inside the cab. Stopping distance and brake pedal depression continue to worsen as time passes. This has now become so bad that we can no longer drive the car safely.

- Plano, TX, USA

Brakes feel hard and vehicle brakes slower than it should. It took a much longer distance to stop. Hissing sound from pedal. Found numerous descriptions on similar problems with brake booster tear. Don't understand why this was not recalled.

- Syracuse, NY, USA

Power brakes are going out. While driving the power assist on the brakes goes out. You have to push as hard as you can to get any stopping ability and then they will work fine again. This happens randomly but frequently. The car has 75,000 miles.

- Greenville, SC, USA

The brakes have become very hard to push, it takes all my might to get car to stop, and there is a squealing sound when pedal is pushed all the way down. Feels as if car isn't going to stop.

- Apple Valley, MN, USA

Brake failure at 60K miles (possibly earlier). I bought the vehicle from a dealer 2 months ago and was told front and rear pads and rotors had already been replaced. They felt inconsistent but I thought they needed to settle in. Then the power boost began to fail and a high pitched whining noise comes from the booster if the pedal is held down. It has lurched forward with my footrr on the pedal while at a full stop. I now put it in neutral when at a stop. Getting it to stop is the problem. Very, very dangerous.

- Columbia, SC, USA

We have noticed the difficulty in depressing the brake pad along with the hissing noise over the past 1 month and it has progressively became stronger. Initially you brush it off thinking you are imagining it. Today on a hill there was an accident so traffic was barely moving, I started to leave more and more distance with the vehicle in front of me as it was becoming increasingly difficult to depress the brakes. Finally I hear a strange noise and then complete quiet and my teenage daughter notices too and as I release the brake to move I realize the car engine had died (the engine has never given any indication of issues before) but the engine dash lights weren't on indicating there was not power which of course means no power steering either, a quick shift to N and restart and all is fine the rest of the way home. The hissing noise and difficult depression continued however while on the hill when I did press hard enough for the brakes to respond they did so as though bypassing the anti-lock system as they would jolt into the stop. Very concerning as the distance to stop has increased, what if a person walked in front of me much less if I'm on the freeway and come upon a sudden need to stop. But here it is a Saturday evening and how and when can I deal with an obvious safety issue that clearly is repeated. I wonder how many out there have not taken the time to report, have spent much on repairs or simply traded in their vehicle to come in to the hands of some other unsuspecting consumer. Action truly is needed before someone's lives are changed forever.

- Renton, WA, USA

Brakes feel hard and vehicle brakes slower than it should. It took a much longer distance to stop. Hissing sound from pedal. Found numerous descriptions on similar problems with brake booster tear. Don't understand why this was not recalled.

- Shakopee, MN, USA

With no warning at all the power brakes stopped working. To stop the car you have to almost stand on the brakes. When you push on the brake pedal you also hear a very faint hissing noise. This is very dangerous as there is no warning of the brake failure. Unless you are a very strong person there is no way to stop the car in an emergency.

- Greensburg, PA, USA

The brakes have become very hard to push, it takes all my might to get car to stop, and there is a squealing sound when pedal is pushed all the way down. Feels as if car isnt going to stop. This occured on the highway and I was lucky I was able to downshift to slow car and get off highway

- Long Beach, NY, USA