2021 Mazda MAZDA3 problems

Filed Nov 5, 2026 · Transmission · OR

Radiator leaking coolant requiring replacement at 60k miles. Mazda updated the part which means they know it's bad, should be fixed for free for all affected owners.

Filed Oct 13, 2026 · Electrical · ME

While driving to work, the dashboard displayed “Charging system malfunction, pull over.” The driver pulled over safely. The vehicle has electric power steering, so a loss of charging power while driving could reduce steering assist and cause the vehicle to stall in traffic. This happened three days after a Mazda dealer replaced the front passenger-side lower control arm. That part had failed at 111,777 miles, causing clunking under braking and making the car unsafe to drive (previously reported to the federal safety agency). This is the second safety-related failure on this vehicle in two weeks. The vehicle is again off the road pending dealer diagnosis. Reported to Mazda Customer Experience, case #00503860.

Filed Oct 8, 2026 · Suspension · ME

Vehicle: 2021 Mazda Mazda3 VIN: [XXX] Mileage at failure: 111,777 Date the problem started: [date you first heard the clunk] Location: [town], [XXX] Crash / fire / injury / death: No Was the vehicle moving? Yes Component: Suspension: Front (Lower Control Arm) Description: The front passenger-side lower control arm on my 2021 Mazda3 failed at 111,777 miles. The car began clunking loudly when braking and while driving. My mechanic inspected the car on a lift, identified the lower control arm as the source, and told me the car was not safe to drive. He suspects a failed or defective part. A bolt hole near the rear control arm mount was also found empty, with rust on the threads. The lower control arm holds the front wheel in place and carries the load under braking and steering. A failure like this could cause loss of steering control. The car has been off the road since the failure. I live in [XXX], where roads are heavily salted in winter. Mazda has issued earlier recalls on other models for corrosion in the front lower control arms that could let the ball joints separate. I’m concerned this may be a similar issue. I reported this to Mazda Customer Experience on October 8, 2026 (case number: [number]). The car is scheduled for diagnosis at Thompson’s, an authorized Mazda dealer in [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 28, 2026 · Transmission · OR

Making sharp right turn out of parking lot under hard acceleration, car suddenly made terrible grinding sound that shook the whole car. Continued driving, within another quarter mile the whole car started shaking again with loud noise. Had car towed to Mazda where they discovered that the rear differential had failed. Rear differential replaced under warranty. Noticed faint high pitched sound coming from rear in months leading up to incident. Had differential and transfer case fluid changed less than 1000 miles and 1 month before incident making me wonder if fluid was underfilled/wrong fluid used or the diff was just bad.

Filed Sep 28, 2026 · Engine · OR

Low engine oil message appeared on dash. Had car towed to Mazda. Had valve stem seals replaced under warranty.

Filed Sep 28, 2026 · Brakes · 45,946 miles · OR

Car made grinding sound with notable vibration when starting to move after shifting into drive. Felt like brakes weren't releasing. Had car towed to dealership where they diagnosed that the front left brake shim was damaged and making contact with the rotor, had to pay to fix it out of pocket.

Filed Jan 25, 2026 · Transmission · MO

My rear differential case cracked, anytime the four wheel drive system was engaged the entire drivetrain would lock up. Luckily we were only on side roads so going less than 30 mph if we had been on the highway when this happened we could have been in an accident or lost control. The dealer did confirm the problem and it was fixed under an extended warranty. There was no warning just all of a sudden a loud bang and all the wheels locked up. I have a copy of the video inspection done at the dealer if there's anyway to send that. I can get a copy of the repair invoice if needed

Filed Oct 27, 2025 · Suspension · CA

At 31,000 miles the control arm lower ball joints are torn on both lower. They must be replaced. This is a safety hazard. This should not be an issue with low mileage on this car.

Filed May 27, 2025 · Transmission · MO

I was driving when all the sudden there was a loud bang sound. The differential housing cracked. The when awd is demanded the rear diff was was locking up instead of engaging. Luckily we were just on city streets and not on the highway as this rear wheel locking up could cause a crash. Mazda wasn't very helpful with the replacement. Luckily I had a aftermarket warranty but it only paid for a used replacement, which is also failing. I have read lots of stories of this rear differential failure across all types of Mazda's from this era and really wish they would do the correct thing and resolve the problem.

Filed Apr 23, 2025 · Engine · PA

Spontaneous loss of power while driving on highway. Check engine light came on. Speed limited by car. Continues to vibrate especially at idle from cold start. Code P0304 intermittently popping up.