AI-generated · grounded in NHTSA data

Reliability & 5-year cost of ownership — 2021 Mazda Cx-9

Overall rating NHTSA-grounded

Average

Estimated 5-year repair + maintenance cost: $4,000–$9,000

The 2021 Mazda CX-9 has an average reliability rating, with concerns primarily focused on the engine and brakes, which lead the complaint counts. Potential recall issues with seat assembly further impact its reliability.

Most-common failures

Part Typical mileage Cost range Frequency
engine30,000–50,000 miles$500–$2,500common
service brakes40,000–60,000 miles$300–$1,500occasional
forward collision avoidance20,000–40,000 miles$400–$1,200occasional

Scheduled maintenance to budget

Routine items every owner should plan for.

  • oil and filter changes
  • brake pad replacement
  • tire rotations and balancing
  • coolant flush
  • transmission fluid change

Warning signs to watch for

Symptoms that signal a major upcoming repair.

  • engine misfires or stalling
  • reduced braking performance
  • unexpected forward collision warnings

Generated by gpt-4o on 8/19/2026. Cost ranges are conservative estimates that account for typical regional variation.