BMW E60 M5: V10 (S85) Engine Problems — Quick Breakdown
Quick Summary
The naturally aspirated S85 V10 is an engineering masterpiece from BMW, but running one takes a particular approach. The main risks are worn main bearings and rod bearings, oiling problems at high rpm, and a loosening crankshaft center bolt. Regular oil changes with the correct specification and preventive bearing replacement at 50,000–62,000 miles are the key to a long engine life.
The Problem
You get into an E60 M5, fire up the engine—and hear a metallic knock on a cold start. That’s the first sign of bearing wear, the most common ailment of this V10. An engine that revs to 8,250 rpm runs at its limits, and maintenance mistakes turn into catastrophe fast.
Symptoms
- Metallic knock on cold start
- Dropping oil pressure
- Unusual noises at high rpm
- Metal shavings in the oil
- Power loss and an unstable idle
- Camshaft sensor fault codes
Causes
The oil system takes a colossal beating at extreme rpm. The oil pump has to hold stable pressure even at 8,000+ rpm, but during sustained operation above 6,000 rpm it can’t keep up with oil delivery to the critical components. The rod bearings suffer most—they sit farthest from the pump.
The crankshaft center bolt secures the crankshaft’s position relative to the camshafts. Over time it loosens from vibration and cyclic loading, which shifts the valve timing.
The Fix
Oil Changes — Priority No. 1
The S85 needs oil with the LL-01 or LL-04 approval, in 10W-60 or 5W-50 viscosities. That high viscosity protects the engine at high temperatures and high rpm.
The change interval is 4,300–6,000 miles, or 3,100 miles with hard track use. The engine can consume up to 1 quart of oil per 620 miles, so check the level before every long drive.
Oil Pressure Monitoring
Fit an oil pressure sensor if the car didn’t come with one from the factory. Pressure dropping below 1 bar at idle or below 3 bar at rpm is a red flag that demands immediate diagnosis.
Preventive Bearing Replacement
Replacing the main bearings and rod bearings is recommended at 50,000–62,000 miles, even with no obvious symptoms. Prevention costs less than a full engine rebuild after a thrown rod.
Checking the Crankshaft Center Bolt
Check the torque spec of the crankshaft center bolt at every major service. The spec is 385 lb-ft. If the bolt has loosened, replace it and torque it to spec.
Cost of the Work
| Job | Cost |
|---|---|
| Bearing set (OEM) | Significant parts cost |
| Bearing replacement labor | Substantial cost for a major job |
| Crankshaft center bolt replacement | Moderate cost |
| Full repair (bearings + bolt + oil) | Very significant cost |
| Used S85 engine | Extremely high cost |
Prevention / Buyer’s Checklist
- Listen to the engine cold: a knock or tick means it’s time for deeper diagnostics
- Ask for the service history: the ideal record shows oil changes every 4,300–6,000 miles with genuine BMW oil
- Have the crankshaft center bolt torque checked on a lift
- Check VANOS operation: camshaft fault codes and a fluctuating idle point to valve timing problems
- On the test drive, watch for idle stability, throttle response, and any noise while pulling past 6,000 rpm
- Trust the work only to shops that specialize in M cars
The Bottom Line
The S85 V10 is a one-of-a-kind naturally aspirated engine that delivers an unforgettable experience—and demands a responsible owner. Regular oil changes with the correct specification, thoughtful driving, and preventive bearing replacement at 50,000–62,000 miles are the main conditions for a long engine life. Spend the money on prevention instead of facing an extremely expensive engine replacement.