2020 BMW 840i

The 2020 BMW 840i is a luxury grand tourer known for its stylish design, comfortable ride, and powerful performance. The 840i comes with a 3.0-liter turbocharged inline-6 engine producing 335 horsepower and 368 lb-ft of torque. Other engine options for the 8 Series include a 4.4-liter twin-turbo V8 in the M850i and the high-performance M8. The 840i is paired with an 8-speed automatic transmission. Owners typically praise the 840i for its sleek looks, comfortable interior, and smooth driving experience. Some common criticisms include the rear seat space being limited, the complicated infotainment system, and the high price point.

Engine

3.0L Turbocharged Inline-6 (B58)

• Coolant Leaks
  • Description/Symptoms: Coolant leaks are a somewhat common issue on the B58 engine, often manifesting as a low coolant warning or visible coolant pooling under the vehicle. Leaks may originate from the plastic coolant hoses, expansion tank, or water pump.
  • Solution: Replacing the leaking coolant hoses, expansion tank, or water pump with updated parts, preferably those made of more durable materials.
  • Estimated Cost to Fix: $200 - $1000+ depending on the source of the leak and parts replaced.
  • Recalls: None Found
• Oil Filter Housing Gasket Leak
  • Description/Symptoms: Oil leaks around the oil filter housing. This is often gradual, but can become significant over time. Visible oil around the housing and a burning oil smell may be present.
  • Solution: Replacing the oil filter housing gasket.
  • Estimated Cost to Fix: $200 - $500+
  • Recalls: None Found

Transmission

8-Speed Automatic (ZF 8HP51)

• Rough Shifting
  • Description/Symptoms: Some owners have reported experiencing rough or hesitant shifting, particularly at lower speeds. This can feel like a noticeable jerkiness during gear changes.
  • Solution: In some cases, a transmission software update may resolve the issue. In more severe cases, replacement of solenoids or valve body components might be necessary.
  • Estimated Cost to Fix: $200 (software update) - $2,000+ (valve body replacement)
  • Recalls: None Found

Suspension

• Adaptive Damper Malfunctions
  • Description/Symptoms: The adaptive dampers can sometimes develop issues, leading to a harsher or less controlled ride. Warning lights related to the suspension system may appear on the dashboard.
  • Solution: Diagnosis to determine the faulty damper, followed by replacement of the affected damper.
  • Estimated Cost to Fix: $500 - $1500+ per damper.
  • Recalls: None Found

Electrical

• Infotainment System Glitches
  • Description/Symptoms: Freezing, lagging, or unexpected reboots of the iDrive infotainment system.
  • Solution: Software updates are often the first step, but in some cases, the head unit may need to be replaced.
  • Estimated Cost to Fix: $0 (software update) - $1,500+ (head unit replacement)
  • Recalls: None Found
• Sensor Failures (Parking Sensors, etc.)
  • Description/Symptoms: Malfunctioning parking sensors, leading to inaccurate readings or complete failure.
  • Solution: Replacing the faulty sensor.
  • Estimated Cost to Fix: $200 - $500+ per sensor.
  • Recalls: None Found

Exterior

No Issues Found

Interior

• Rattling/Squeaking Noises
  • Description/Symptoms: Rattling or squeaking noises emanating from the dashboard, door panels, or rear deck.
  • Solution: Identifying the source of the noise and applying sound-deadening material or tightening loose components. This is often a process of trial and error.
  • Estimated Cost to Fix: $100 - $500+ depending on the complexity and labor involved.
  • Recalls: None Found

Summary

The 2020 BMW 840i can suffer from a range of issues. While the B58 engine is generally reliable, it can have coolant and oil leaks, which are moderately expensive to fix. The transmission can exhibit rough shifting. Electrical issues mostly include glitches with the infotainment system. Suspension issues are caused by adaptive damper malfunctions. Interior rattles are mostly minor issues that can be addressed with some effort. Overall, the 2020 BMW 840i is a well-rounded vehicle that is a pleasure to drive but can have a few issues that will need to be addressed.