BMW M8 F92 Reliability: The Flagship's Flaws
Common Failure Points & Costs
| Component | Failure Mileage | Symptom | Est. Cost (USD) | Risk Level |
|---|---|---|---|---|
| Coolant Expansion Tank | 20k - 40k miles | Leak at seams | $600 - $1,500 | High |
| Integrated Brake System | Random | Loss of brake feel, warning light | $2,500 (Recall often covers) | Medium |
| Windshield Cracks | Random | Stress cracks (HUD glass) | $2,000 (OEM HUD Glass) | Medium |
| S63TU4 Rod Bearings | 100k+ | Rare | $3,000 | Low |
Reliability Verdict
The M8 shares the robust S63TU4 with the F90 M5, making it mechanically reliable. The main risks are the coolant tank (fixable) and the high cost of GT-specific parts (laser lights, carbon core, glass). Depreciation is the biggest cost of ownership.
BMW M8 F92 Reliability: The Flagship’s Flaws
The BMW M8 (F91/F92/F93) is the flagship. It replaced the M6. It uses the same powertrain as the F90 M5 but wraps it in a stunning, low-slung GT body.
It is fast (0-60 in 2.5s recorded). It is luxurious. And thanks to the S63TU4 engine, it is surprisingly reliable.
1. Engine: S63TU4 (The Good One)
Like the F90 M5, the M8 uses the S63B44T4.
- Rod Bearings: Not a major concern.
- Injectors: Solid.
- Cooling: Excellent.
The Weakness: Coolant Tank
Yes, the M8 suffers from the same coolant expansion tank leak as the M5.
- Inspect: Check the tank seams for white residue.
- Fix: Replace or upgrade to aluminum.
2. Brake-By-Wire System
The M8 uses an “Integrated Brake System” (Drive-by-wire brakes). There is no physical vacuum connection between the pedal and the master cylinder (mostly).
- Feel: Adjustable (Comfort/Sport).
- Reliability: Early models (2020) had some software glitches resulting in a “Brake System Malfunction” warning.
- Fix: Software updates usually cure it. Hardware failure is rare but expensive ($2,500 unit).
3. GT-Specific Issues
The M8 is unique.
- Laser Lights: Optional. Incredible performance. $7,000 per headlight to replace. Do not crash.
- Windshield: The glass is huge, acoustic, and HUD-compatible. It is prone to stress cracks. Replacement is $2,000+.
- Carbon Core: The chassis uses carbon fiber structurally. Repairing accident damage is astronomically expensive.
4. Depreciation: The Silent Killer
The M8’s biggest reliability issue is its ability to retain value.
- Drop: M8s lost 40% of their value in 3 years.
- Opportunity: This makes them a screaming bargain on the used market. You can get a $160k car for $90k.
5. Buying Guide
- Coupe vs Gran Coupe: The Gran Coupe (4-door) holds value better and looks better to many eyes.
- Carbon Buckets: Avoid them for a daily driver. They are hard to get in/out of. The standard M seats are perfect.
- Tires: 20-inch Michelin PS4S. Budget $1,800 a set.
6. Conclusion
The M8 is a “Super-M5.” It drives similarly but looks like a supercar. It shares the solid reliability of the S63TU4. If you can stomach the depreciation (or buy used), it is the ultimate BMW.
Expert Buying Advice
Buy a Gran Coupe for resale value. Ensure the coolant tank has been replaced. Check for windshield chips (HUD glass is expensive). Enjoy one of the best GT cars ever made.