2021 INFINITI QX80

The 2021 INFINITI QX80 is a full-size luxury SUV known for its spacious interior, comfortable ride, and powerful V8 engine. It offers a refined driving experience, upscale features, and a commanding presence on the road. The QX80 is powered by a 5.6-liter V8 engine producing 400 horsepower and 413 lb-ft of torque, paired with a 7-speed automatic transmission. While the QX80 is appreciated for its luxurious appointments and strong performance, some owners have reported issues ranging from minor electronic glitches to more significant mechanical problems. Some common complaints include issues with the infotainment system, sensor malfunctions, and concerns about fuel economy.

Engine

5.6L V8 Engine

• Excessive Oil Consumption
  • Description/Symptoms: Owners report a noticeable decrease in engine oil levels between oil changes, requiring frequent topping off. Blue smoke may be visible from the exhaust, indicating oil burning.
  • Solution: Possible solutions range from replacing the Positive Crankcase Ventilation (PCV) valve to more extensive repairs such as piston ring replacement. A compression test can help diagnose the severity of the issue.
  • Estimated Cost to Fix: $100 (PCV Valve) - $3,000+ (Piston Ring Replacement)
  • Recalls: None Found
• Valve Train Noise
  • Description/Symptoms: Ticking or knocking noises emanating from the engine, particularly at idle or low speeds. Could be related to worn lifters or issues with the variable valve timing (VVT) system.
  • Solution: Diagnosis is critical to determine the source of the noise. Could require replacement of lifters, VVT components, or timing chain components.
  • Estimated Cost to Fix: $500 - $2,500+
  • Recalls: None Found

Transmission

7-Speed Automatic Transmission

• Harsh Shifting
  • Description/Symptoms: Abrupt or jerky shifts between gears, particularly noticeable during acceleration or deceleration.
  • Solution: A transmission fluid flush and software update could help resolve the issue. In some cases, valve body replacement or transmission rebuild may be necessary.
  • Estimated Cost to Fix: $200 (Fluid Flush) - $3,000+ (Transmission Rebuild)
  • Recalls: None Found
• Transmission Slipping
  • Description/Symptoms: Engine RPMs increase without a corresponding increase in vehicle speed, indicating the transmission is not properly engaging gears.
  • Solution: Start with a transmission fluid level check and inspection. If the fluid is low or contaminated, a fluid flush may help. More severe cases may require valve body repair or replacement, or even a complete transmission overhaul.
  • Estimated Cost to Fix: $150 (Fluid Top-off) - $4,000+ (Transmission Overhaul)
  • Recalls: None Found

Suspension

• Air Suspension Failure (if equipped)
  • Description/Symptoms: Vehicle sits unevenly, air compressor runs constantly, error messages appear on the dashboard related to the suspension system.
  • Solution: Diagnose the leak(s) in the air lines, air springs, or compressor. Replacement of faulty components is typically required.
  • Estimated Cost to Fix: $500 - $2,000+ per component
  • Recalls: None Found

Electrical

• Infotainment System Freezing/Crashing
  • Description/Symptoms: The infotainment screen freezes, becomes unresponsive, or restarts unexpectedly.
  • Solution: Try a system reset by holding the power button. A software update may be available from the dealer. In some cases, the infotainment unit may need to be replaced.
  • Estimated Cost to Fix: $0 (Reset/Update) - $1,500+ (Replacement)
  • Recalls: None Found
• Sensor Malfunctions (Blind Spot Monitoring, Parking Sensors, etc.)
  • Description/Symptoms: False alarms, intermittent failures, or complete loss of functionality from driver assistance systems.
  • Solution: Diagnose the specific sensor that is malfunctioning. Check wiring connections and sensor alignment. Replacement of the faulty sensor is often necessary.
  • Estimated Cost to Fix: $200 - $800+ per sensor
  • Recalls: None Found

Exterior

• Automatic Tailgate Issues
  • Description/Symptoms: Tailgate fails to open or close properly, makes unusual noises, or stops mid-operation.
  • Solution: Check the tailgate struts and latch mechanism. Lubricate moving parts. The motor or control module may need to be replaced.
  • Estimated Cost to Fix: $100 (Lubrication) - $1,000+ (Motor/Module Replacement)
  • Recalls: None Found

Interior

• Sunroof/Moonroof Problems
  • Description/Symptoms: Sunroof gets stuck, makes grinding noises, or leaks water.
  • Solution: Check the sunroof tracks for debris or obstructions. Lubricate the tracks and seals. The motor or linkage may need to be replaced.
  • Estimated Cost to Fix: $100 (Lubrication) - $800+ (Motor/Linkage Replacement)
  • Recalls: None Found

Summary

The 2021 INFINITI QX80, while a luxurious and powerful SUV, has some common issues. The engine can experience oil consumption and valvetrain noise, which can be costly to repair if not addressed promptly. The transmission can suffer from harsh shifting and slipping, potentially requiring fluid changes or more substantial repairs. Electrical glitches with the infotainment system and sensor malfunctions can also be frustrating. Suspension issues may also be present on vehicles that are equipped with air suspension. Overall, these issues range in severity and cost, so buyers should be aware of these potential problems and inspect used models carefully before purchase.