BMW F90 M5: Review, Problems, S63 Engine Life, and Whether to Buy in 2025
Quick Summary
BMW F90 M5 is the last “true” M5 without a hybrid system, built from 2017 to 2023. Under the hood sits a twin-turbo V8 S63B44T4 making up to 617 hp (625 PS) in Competition trim. With proper care, the engine goes 93,000–124,000 miles, but it demands attention to the cooling system, ignition coils, and VANOS solenoids. This article is for anyone considering a used F90 M5.
The Problem
You’re looking at buying an F90 M5 — a supercar wrapped in a practical sedan body. But before you put money down, you need to understand the weak spots of the S63B44T4, what ownership really costs, and which failures can turn your budget into rubble. Here’s the breakdown.
Symptoms
- Hard starting and hesitation on throttle
- Warning lights on the dashboard
- Engine overheating, coolant leaks
- Misfires, rough running
- Power loss, unstable idle
- Increased oil consumption
Causes
S63B44T4 is BMW’s final version of the twin-turbo V8, used through 2023. The engineers learned from previous generations, and this engine is considered the most reliable version. But the design traits remain: high thermal loads and cylinder pressures take their toll.
Increased oil consumption is normal for high-output turbocharged V8s. Under hard driving, consumption can reach about 1 quart per 620–930 miles. That’s not a defect — it’s a design characteristic you simply have to account for.
Rod bearing wear is a problem familiar from older S63s. On the F90 it’s less critical, but with aggressive driving and infrequent oil changes, the bearings wear faster. Regular diagnostics and timely oil changes reduce the risk.
The Fix
Pre-Purchase Inspection
- Check VANOS — VANOS solenoid failures are one of the most expensive problems. A failure causes power loss and error codes.
- Check the fuel system — low-pressure pump failure is a common issue.
- Check the cooling system — the expansion tank can crack or leak coolant.
- Check the service history — especially oil change intervals.
- Test drive through all modes — xDrive, rear-wheel drive, track mode.
Repair and Maintenance
| Component | Problem | Cost |
|---|---|---|
| VANOS system | Solenoid replacement | Significant expense |
| Fuel system | Low-pressure pump replacement | Moderate expense |
| Cooling system | Expansion tank replacement | Minor expense |
The key rule: change the oil every 5,000–6,000 miles. Using quality synthetic oil with the correct approvals is critical. Under aggressive driving, shorten the interval to 4,300–5,000 miles.
Spark plugs need replacement every 25,000–31,000 miles, and coils can fail sooner.
Prevention / Checklist
- Check the oil level regularly, top off as needed
- Inspect the expansion tank at every service
- Replace spark plugs every 25,000–31,000 miles
- Run VANOS and fuel system diagnostics at the first sign of trouble
- Use gasoline with a pump octane rating of at least 93 (98 RON)
- When buying, go for a Competition or LCI version
Bottom Line
The F90 M5 is a car for those who value pure driving feel and are willing to pay for the pleasure. The S63B44T4 is reliable with proper care, and the lack of a hybrid system simplifies maintenance. In 2025, it’s one of the last chances to buy a true M5 without electrification. Find a well-documented example, get a pre-purchase inspection — and don’t hesitate.
📖 Full research: BMW S63: Engine, Life, Problems — an in-depth technical breakdown with component subtypes, control unit specs, and engineering details.
Technical Data
Torque spec (lb-ft): 553 lb-ft