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2021 Mazda Cx 9 Recalls, Issues & Maintenance

The 2021 Mazda Cx 9 carries 1 open NHTSA recall — most recently covering mid/rear assembly. Owners report 4 recurring issue clusters, led by “Excessive engine oil consumption.” Mazda's Skyactiv engines use unusually high compression ratios (13:1 to 16:1) and require strict adherence to oil intervals — extending oil life on a Skyactiv engine accelerates carbon buildup on intake valves. Mazda's published Schedule 1 (severe) covers most US driving conditions. Mazda3, CX-5, CX-30, and CX-50 share the Skyactiv-G platform.

1 Open Recall

Source: NHTSA

SEATS:MID/REAR ASSEMBLY

Campaign #21V750000 · Sep 27, 2021

Issue: Mazda North American Operations (Mazda) is recalling certain 2020-2021 CX-9 vehicles equipped with 60/40 split bench second-row seats. The left-side second-row seat may unexpectedly slide forward during a crash. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 210, "Seat Belt Assembly Anchorages."

Risk: A seat that slides forward during a crash can transfer excessive force onto a belted occupant, increasing their risk of injury.

Fix: Dealers will replace the internal parts of the affected second-row seats, free of charge. Owner notification letters were mailed November 4, 2021. Owners may contact Mazda customer service at 1-800-222-5500, Option 4. Mazda's number for this recall is 5221I.

Recall data refreshed Sep 6, 2026.

Known issues for this vehicle

What drivers and federal regulators have officially reported about the 2021 Mazda Cx 9.

Reported to NHTSA

Excessive engine oil consumption

ENGINE

17 NHTSA complaints · 2022-06 → 2025-06

“New Mazda vehicle engine is consuming approximately 1 quart of oil, approximately every 3,500 miles. No recall for this yet, however Mazda technical service bulletin TSB # 01-012/21 admits this is a common and known issue for this vehicle…”
— Owner report, NHTSA ODI #11473943
“Massive oil consumption. Uses 1 quart or more of engine oil at around 3,000 miles after oil change. Low oil light comes on...”
— Owner report, NHTSA ODI #11481982
“Consumes over 2 quarts of oil between recommended oil changes. The dealer made excuses about needing to use a different oil but it has not improved the problem. The warning light for low oil went off after less than 3000 miles. It was 2 quarts down.”
— Owner report, NHTSA ODI #11595406

Read all complaints on NHTSA →

Loss of motive power at highway speed

ENGINE

2 NHTSA complaints · 2023-02 → 2024-08

“The contact owns a 2021 Mazda CX-9. The contact stated that while driving at 60 MPH or exceeding 60 MPH, the vehicle would lose motive power and stall without warning. The contact stated that he would coast to the side of the road and the vehicle would restart…”
— Owner report, NHTSA ODI #11505764
“The contact owns a 2021 Mazda CX-9. The contact stated that while accelerating quickly and entering the highway, there was no motive power to the vehicle. While crossing the highway in the right lane, driving at 65 MPH, the vehicle in front moved over…”
— Owner report, NHTSA ODI #11608556

Read all complaints on NHTSA →

i-Activsense system malfunction and limp mode

FORWARD COLLISION AVOIDANCE

2 NHTSA complaints · 2023-10 → 2024-11

“On [XXX], [XXX], [XXX] I was driving on an interstate highway with a 65 mph speed limit with no warning and received the following codes which slowed the vehicle to the limp mode. 1) Smart Brake Support and Forward Obstruction Warning…”
— Owner report, NHTSA ODI #11627970
“6/29/2023--Vehicle stopped suddenly with i-ACTIVESENSE system malfunction, Dynamic Stability Control malfunction, Engine malfunction, engine output reduced, Front radar sensor malfunction. Dealer said these faults due to bad battery--replaced battery per Service Manager…”
— Owner report, NHTSA ODI #11548334

Read all complaints on NHTSA →

Driver airbag non-deployment in frontal collision

AIR BAGS

2 NHTSA complaints · 2022-12 → 2023-05

“2021 Mazda CX-9 Frontal collision at a speed between 10-20 mph. Car shut down after collision and was not drivable. Concern is the driver side airbag did not deploy. (Neither did passenger but there was no person in the passenger seat)”
— Owner report, NHTSA ODI #11523765
“The driver side airbag did not deploy in a front end collision on the drivers side. When approaching a vehicle that had come to a sudden and complete stop, the brakes were applied hard to the Mazda CX-9 in order to stop, but after about 1 second they just totally let go…”
— Owner report, NHTSA ODI #11495745

Read all complaints on NHTSA →

Issues on other model years

Source: NHTSA Office of Defects Investigation (ODI). Complaint data refreshed Sep 11, 2026. Investigation data refreshed Sep 11, 2026.

We display NHTSA's record with attribution; we don't editorialize on what these complaints mean for any specific vehicle.

Essential maintenance

Critical for safety and preventing major damage

Engine Oil & Filter

Every 5,000 mi

Replace 0W-20 full-synthetic oil every 5,000 miles under Schedule 1. Schedule 2 (highway-only): 7,500 miles. Mazda CX-50 Turbo and CX-9: 5,000 miles regardless of schedule.

Estimated cost — typical U.S. ranges

Dealer

~$120–$160

Shop

~$85–$115

DIY

~$25–$55

Full synthetic costs more than conventional. 5-quart 0W-20 + filter is the typical bill.

Tire Rotation

Every 7,500 mi

Rotate tires every 7,500 miles. AWD CX-5, CX-50, and CX-9: 5,000 miles to prevent uneven wear from front-biased AWD coupling.

Estimated cost — typical U.S. ranges

Dealer

~$85

Shop

~$60

DIY

Free

Often free at the shop where you bought the tires — worth asking before paying.

Brake Inspection

Every 7,500 mi

Inspect brake pads, rotors, and parking brake at every oil change. Mazda3 and CX-5 front pads typically last 35,000-50,000 miles.

Estimated cost — typical U.S. ranges

Dealer

~$85

Shop

~$60

DIY

Free

Most shops do this free as a courtesy with any service. Don't pay separately if you can avoid it.

Brake Fluid

Every 30,000 mi

Replace DOT 3 brake fluid every 30,000 miles or 36 months.

Estimated cost — typical U.S. ranges

Dealer

~$180–$200

Shop

~$125–$140

DIY

~$10–$25

DOT 3 or 4 — match the cap. Vacuum bleeders make this a one-person DIY.

Important maintenance

Keeps your vehicle running smoothly and efficiently

Engine Air Filter

Every 30,000 mi

Replace engine air filter every 30,000 miles. Skyactiv-G direct injection is sensitive to airflow restriction — inspect at every oil change.

Estimated cost — typical U.S. ranges

Dealer

~$60–$95

Shop

~$45–$70

DIY

~$15–$40

5-minute job on most cars; the airbox lid usually has clips, no tools needed.

Automatic Transmission Fluid

Every 60,000 mi

Replace ATF every 60,000 miles severe / 100,000 normal. Use Mazda FZ ATF — substitutes cause harsh 1-2 shifts and torque converter shudder.

Estimated cost — typical U.S. ranges

Dealer

~$330–$500

Shop

~$235–$355

DIY

~$60–$180

Some sealed transmissions have no dipstick — fill is precise and best left to a shop. Many drivers can still DIY drain-and-fill.

Spark Plugs

Every 60,000 mi

Iridium spark plugs every 60,000 miles on Skyactiv-G 2.0L and 2.5L. CX-50 Turbo and CX-9 Turbo: 45,000 miles.

Estimated cost — typical U.S. ranges

Dealer

~$285–$390

Shop

~$200–$275

DIY

~$25–$100

Iridium plugs cost more but last 100k+ miles. V6/V8 access varies wildly — some are tough.

FL-22 Long-Life Coolant

Every 60,000 mi

Mazda FL-22 (yellow): first change at 120,000 miles or 10 years, then every 60,000. Do not substitute — silicate-free formula prevents water pump damage on Skyactiv engines.

Estimated cost — typical U.S. ranges

Dealer

~$285–$330

Shop

~$200–$235

DIY

~$25–$60

Use the manufacturer-specified coolant — wrong color/chemistry can damage the cooling system.

Transfer Case / Rear Diff (AWD)

Every 60,000 mi

AWD CX-5, CX-50, CX-9: replace transfer case fluid and rear diff fluid every 60,000 miles.

Estimated cost — typical U.S. ranges

Dealer

~$105–$140

Shop

~$75–$100

DIY

~$15–$40

AWD/4WD vehicles only. Easy drain-and-fill on most platforms.

Recommended maintenance

Extends the life of your vehicle and improves comfort

Cabin Air Filter

Every 15,000 mi

Replace cabin air filter every 15,000 miles. Behind the glove box on Mazda3, CX-5, CX-30, and CX-50.

Estimated cost — typical U.S. ranges

Dealer

~$60–$95

Shop

~$45–$70

DIY

~$15–$40

Usually behind the glovebox. Shops charge labor for a 10-minute job — easy DIY win.

Fatal crash history & reported problems

Occupant deaths in fatal crashes (FARS)

3 crashes 2010–2024

FARS counts every occupant death in a fatal crash, whatever the cause — it does not mean the vehicle was at fault or defective. Counts are not adjusted for how many of each vehicle are on the road. How to read this number

Owner-reported problem signals

Separate from the federal fatality data above: complaints owners filed with NHTSA about this year and model. These are reports of problems, unverified, and are counted here only as signals.

7

complaints mentioning a crash

0

complaints mentioning a fire

Reviewed known issues for this vehicle·Open recalls for this vehicle

Typical U.S. ranges. Actual quotes vary by shop, parts choice, and vehicle condition.

How we estimate: Dealer = OEM parts × 1.4 + labor × $165/hr. Shop = parts + labor × $115/hr. DIY = parts only.

This maintenance schedule for the 2021 Mazda Cx 9 reflects Mazda's published service intervals. Your actual service needs may vary based on driving conditions, climate, and vehicle usage. Always consult your owner's manual for model-specific recommendations.

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