AI-generated · grounded in NHTSA data
Reliability & 5-year cost of ownership — 2004 Bmw 6 Series
Overall rating NHTSA-grounded
Below average
Estimated 5-year repair + maintenance cost: $8,000–$12,000
The 2004 BMW 6 Series has a below-average reliability rating due to multiple recalls affecting crucial systems like brakes, the electrical system, and the cooling system. These issues could lead to significant safety hazards and increased repair costs over time.
Most-common failures
| Part | Typical mileage | Cost range | Frequency |
|---|---|---|---|
| cooling fan | 50,000–80,000 miles | $300–$600 | common |
| battery cable | 60,000–100,000 miles | $250–$500 | common |
| brake booster | 70,000–110,000 miles | $500–$900 | occasional |
| transmission control module | 80,000–120,000 miles | $400–$800 | occasional |
Scheduled maintenance to budget
Routine items every owner should plan for.
- Oil and filter change
- Brake fluid replacement
- Spark plug replacement
- Cooling system flush
- Fuel filter replacement
Warning signs to watch for
Symptoms that signal a major upcoming repair.
- Overheating engine
- Loose battery connections
- Delayed gear shifts
- Soft brake pedal
Generated by gpt-4o on 8/24/2026. Cost ranges are conservative estimates that account for typical regional variation.