2018 Lexus GS450h

The 2018 Lexus GS450h is a luxury hybrid sedan known for its comfortable ride, refined interior, and fuel efficiency. It features a 3.5-liter V6 engine paired with an electric motor, producing a combined 338 horsepower and delivering smooth and responsive performance. The GS450h only comes with an Electronically Controlled Continuously Variable Transmission (ECVT). Owners generally appreciate the car’s reliability, quiet cabin, and upscale features. Some common dislikes include the somewhat dated infotainment system and the limited trunk space due to the hybrid battery pack.

Electric Motor

3.5L V6 Hybrid System

• Hybrid Battery Degradation
  • Description/Symptoms: Gradual decrease in battery capacity over time, resulting in reduced electric-only range, decreased fuel economy, and potential “check hybrid system” warning light.
  • Solution: Replacement of the hybrid battery pack. In some cases, individual battery modules can be replaced if the pack hasn’t severely degraded.
  • Estimated Cost to Fix: $3,000 - $8,000+ (battery pack replacement). Module replacement can be $500-$1500 depending on labor and module availability.
  • Recalls: None Found
• Inverter Failure
  • Description/Symptoms: The hybrid inverter converts DC voltage from the battery to AC voltage for the electric motor. Failure can lead to complete loss of hybrid system functionality, preventing the car from starting or moving. Warning lights such as “Check Hybrid System” or related codes can appear.
  • Solution: Replacement of the hybrid inverter assembly.
  • Estimated Cost to Fix: $4,000 - $7,000+
  • Recalls: None Found

Transmission

Electronically Controlled Continuously Variable Transmission (ECVT)

• No Issues Found

Suspension

• Adaptive Variable Suspension (AVS) Issues (If Equipped)
  • Description/Symptoms: Failure of the AVS system can result in a harsh or uncomfortable ride. Warning lights related to the AVS system may appear on the dashboard. It can manifest as one strut failing to adjust properly leading to uneven ride quality and handling.
  • Solution: Diagnosis and replacement of faulty AVS components such as shocks/struts or control modules.
  • Estimated Cost to Fix: $800 - $2,000+ per strut depending on the specific component and labor costs.
  • Recalls: None Found

Electrical

• Navigation/Infotainment System Freezing or Crashing
  • Description/Symptoms: The navigation or infotainment system may become unresponsive, freeze, or crash intermittently.
  • Solution: Software update or replacement of the head unit.
  • Estimated Cost to Fix: $100 - $300 for software update (if available). $1,000 - $3,000+ for head unit replacement.
  • Recalls: None Found
• Sensor Malfunctions (Parking Sensors, Blind Spot Monitor, etc.)
  • Description/Symptoms: Malfunctioning sensors can cause false alarms, failure to detect obstacles, or complete system failure.
  • Solution: Diagnosis and replacement of faulty sensors.
  • Estimated Cost to Fix: $300 - $800+ per sensor, depending on location and complexity.
  • Recalls: None Found
• Faulty Wiring Harness
  • Description/Symptoms: Damaged or corroded wiring harnesses, especially in areas exposed to the elements, can lead to a variety of electrical issues, including intermittent sensor malfunctions, lighting problems, and communication errors between modules.
  • Solution: Repair or replacement of the affected wiring harness section.
  • Estimated Cost to Fix: $500-$2,000+ depending on the location and extent of the damage.
  • Recalls: None Found

Exterior

• Automatic High Beam Malfunction
  • Description/Symptoms: The automatic high beam system fails to properly dim or activate the high beams, leading to potentially dangerous driving situations.
  • Solution: Recalibration of the camera/sensor or replacement of the headlight control module.
  • Estimated Cost to Fix: $200 - $800+ depending on the specific cause.
  • Recalls: None Found

Interior

• Sunroof Issues
  • Description/Symptoms: The sunroof may fail to open or close smoothly, get stuck, or make excessive noise.
  • Solution: Lubrication of sunroof tracks, repair or replacement of sunroof motor or associated components.
  • Estimated Cost to Fix: $200 - $1,000+ depending on the specific problem.
  • Recalls: None Found
• Delamination of Dashboard Material
  • Description/Symptoms: Separation of layers of the dashboard material can occur, creating a visible defect. This usually occurs around the seams or edges of the dashboard trim.
  • Solution: Replacement of the dashboard.
  • Estimated Cost to Fix: $1,500-$3,000+
  • Recalls: None Found

Summary

The 2018 Lexus GS450h is a generally reliable vehicle, but it is not without its potential issues. The most concerning problems relate to the hybrid system components, particularly the hybrid battery and inverter, which can be costly to repair or replace. Electrical issues, such as sensor malfunctions and infotainment glitches, can also occur. Suspension problems, if equipped with AVS, can add to maintenance costs. Owners should be aware of these potential issues and factor them into their purchasing decision. The severity of these issues varies, and the cost of repairs can range from a few hundred to several thousand dollars. Regular maintenance and prompt attention to any warning signs can help mitigate potential problems and extend the life of the vehicle.