2021 Mazda Mazda3 power train problems
This is a safety-related system. If you notice symptoms, stop driving and have it inspected.
What owners report
“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.”
NHTSA complaint · filed 11/05/2026
“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…”
NHTSA complaint · filed 09/28/2026
“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 th…”
NHTSA complaint · filed 01/25/2026
“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 ac…”
NHTSA complaint · filed 05/27/2025
“Radiators are failing 3 years after the warranty period. Its leading to coolant lost and perhaps overheating the engine.”
NHTSA complaint · filed 11/26/2024
Unverified owner reports from NHTSA's public complaint database.
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- How common are 2021 Mazda Mazda3 power train problems?
- 5 owners reported power train issues to NHTSA for the 2021 Mazda Mazda3. Counts scale with how many were sold.
- Is there a recall for 2021 Mazda Mazda3 power train problems?
- No matching recall is on file. Check your VIN at nhtsa.gov/recalls for the latest.