2008 BMW M5

The 2008 BMW M5 (E60) is a high-performance sedan known for its powerful V10 engine and engaging driving dynamics. It was offered with a 7-speed SMG (Sequential Manual Gearbox) or a traditional 6-speed manual transmission. The 5.0L S85 V10 engine produces 500 horsepower and 384 lb-ft of torque. Owners often praise the car’s exhilarating performance and unique engine note, but common complaints revolve around high maintenance costs, complex electronics, and the SMG transmission’s reliability.

Engine

S85 5.0L V10

• Rod Bearing Failure
  • Description/Symptoms: A knocking sound from the engine, especially at idle or low RPMs. This is often caused by excessive wear on the rod bearings due to inadequate lubrication. If left unaddressed, this can lead to catastrophic engine failure.
  • Solution: Replace the rod bearings with updated bearings, often performed with ARP rod bolts.
  • Estimated Cost to Fix: $3,000 - $5,000+
  • Recalls: None Found
• Throttle Actuator Failure
  • Description/Symptoms: The engine may run roughly, experience a loss of power, or enter limp mode. A diagnostic trouble code (DTC) related to the throttle actuators will likely be present. These actuators are responsible for controlling the individual throttle butterflies on each cylinder bank.
  • Solution: Replace the faulty throttle actuator. It’s recommended to replace both actuators at the same time, as the other may fail soon after.
  • Estimated Cost to Fix: $2,000 - $4,000+ for both
  • Recalls: None Found
• VANOS High Pressure Oil Line Failure
  • Description/Symptoms: The VANOS (Variable Valve Timing) system relies on high-pressure oil. The VANOS line is known to leak, spray oil onto the exhaust, and even potentially fail.
  • Solution: Replace the VANOS line
  • Estimated Cost to Fix: $800+
  • Recalls: None Found

Transmission

7-Speed SMG (Sequential Manual Gearbox)

• SMG Pump Failure
  • Description/Symptoms: Difficulty shifting gears, slow or jerky shifts, “cog of death” warning light on the dashboard, and potential inability to start the car. The SMG pump is responsible for providing hydraulic pressure to the transmission’s actuators.
  • Solution: Replace the SMG pump, and potentially the relay associated with the pump, as well as checking the hydraulic fluid level and lines.
  • Estimated Cost to Fix: $2,000 - $3,500+
  • Recalls: None Found
• Clutch Failure
  • Description/Symptoms: Slipping clutch, difficulty engaging gears, jerky shifts, and potential inability to move the car. Aggressive driving can significantly reduce the clutch’s lifespan.
  • Solution: Replace the clutch, pressure plate, and throw-out bearing.
  • Estimated Cost to Fix: $2,500 - $4,000+
  • Recalls: None Found

6-Speed Manual Transmission

No Issues Found

Suspension

• EDC (Electronic Damper Control) Failure
  • Description/Symptoms: Stiff or harsh ride, EDC warning light on the dashboard, and potential loss of damping control. The EDC system uses electronically adjustable dampers to provide variable damping based on driving conditions.
  • Solution: Diagnose the specific cause of the EDC failure (e.g., faulty damper, control module, wiring). Replace the faulty component.
  • Estimated Cost to Fix: $800 - $2,000+ per damper
  • Recalls: None Found

Electrical

• Battery Drain Issues
  • Description/Symptoms: The battery may drain quickly, especially when the car is not driven for extended periods. This can be caused by various factors, including a faulty alternator, parasitic draw from aftermarket accessories, or a failing battery.
  • Solution: Diagnose the source of the battery drain using a multimeter. Repair or replace the faulty component.
  • Estimated Cost to Fix: Varies greatly depending on the cause. $100 - $500+
  • Recalls: None Found
• iDrive System Malfunctions
  • Description/Symptoms: The iDrive system may freeze, reboot unexpectedly, or display error messages.
  • Solution: In some cases, a software update can resolve the issue. In other cases, the iDrive controller or screen may need to be replaced.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found

Exterior

• Rust
  • Description/Symptoms: Rust is most common around the rear fenders, undercarriage, and trunk lid.
  • Solution: Rust repair is a multi-step process of sanding down the affected area, applying rust inhibitor, body filler (if needed), primer, and finally paint.
  • Estimated Cost to Fix: $500+
  • Recalls: None Found

Interior

• No Issues Found

Summary

The 2008 BMW M5 is a rewarding but potentially expensive car to own and maintain. Engine and transmission issues, particularly rod bearing failure and SMG malfunctions, can be quite costly. Electrical gremlins and suspension problems can also add to the ownership burden. The severity of these issues can range from minor inconveniences to major mechanical failures. Potential buyers should be aware of these common problems and factor in maintenance costs when considering purchasing a 2008 M5. A pre-purchase inspection by a qualified BMW mechanic is highly recommended.