2021 Mercedes-Benz GLB35 AMG

The 2021 Mercedes-Benz GLB35 AMG is a sporty compact SUV that slots between the standard GLB and the more powerful GLB45 AMG (which was not available until 2021 as a 2021 model year vehicle). The GLB35 AMG comes exclusively with a turbocharged 2.0-liter inline-4 engine producing 302 horsepower and 295 lb-ft of torque, paired with an 8-speed dual-clutch automatic transmission. Owners often praise its practicality, agile handling, and upscale interior. Common criticisms include a firm ride and some infotainment complexity.

Engine

2.0L Turbocharged Inline-4 (M260)

• Coolant Leak from Thermostat Housing
  • Description/Symptoms: Pink or green coolant leaking from the thermostat housing. May cause overheating.
  • Solution: Replacement of the thermostat housing and gasket.
  • Estimated Cost to Fix: $300 - $600+
  • Recalls: None Found
• Excessive Oil Consumption
  • Description/Symptoms: Burning oil, low oil level warnings, and the need to add oil frequently between scheduled oil changes.
  • Solution: In some cases, a software update might help. In more severe cases, piston ring replacement or engine replacement may be required.
  • Estimated Cost to Fix: Software update (covered under warranty if applicable), Piston ring replacement ($3,000 - $6,000+), Engine replacement ($10,000+)
  • Recalls: None Found

Transmission

8-Speed Dual-Clutch Automatic (DCT)

• Rough or Jerky Shifting
  • Description/Symptoms: Harsh shifts, particularly in lower gears or during sudden acceleration. Hesitation during gear changes.
  • Solution: Software update to transmission control module (TCM). If problem persists, clutch replacement or valve body replacement may be necessary.
  • Estimated Cost to Fix: Software update (covered under warranty if applicable), Clutch replacement ($2,000 - $4,000+), Valve body replacement ($1,500 - $3,000+)
  • Recalls: None Found

Suspension

• Premature Wear of Suspension Components
  • Description/Symptoms: Clunking or rattling noises from the suspension, especially over bumps. Uneven tire wear.
  • Solution: Replacement of worn bushings, ball joints, or struts/shocks.
  • Estimated Cost to Fix: $300 - $1,000+ per corner, depending on the parts needing replacement.
  • Recalls: None Found

Electrical

• Malfunctioning MBUX Infotainment System
  • Description/Symptoms: System freezes, reboots unexpectedly, or exhibits lag. Features may be unresponsive.
  • Solution: Software update. In severe cases, replacement of the MBUX control unit may be needed.
  • Estimated Cost to Fix: Software update (covered under warranty if applicable), MBUX control unit replacement ($1,500 - $3,000+)
  • Recalls: None Found
• Sensor Malfunctions
  • Description/Symptoms: Error messages related to various sensors (e.g., parking sensors, blind spot monitoring sensors, etc.).
  • Solution: Diagnostic check to identify the faulty sensor, followed by replacement.
  • Estimated Cost to Fix: $200 - $800+ depending on the sensor and its location.
  • Recalls: None Found

Exterior

• No Issues Found

Interior

• Creaking or Rattling Noises from Dashboard or Trim Pieces
  • Description/Symptoms: Annoying noises emanating from the dashboard or other interior trim, particularly on rough roads.
  • Solution: Locating and securing the loose trim pieces. This may involve adding padding or tightening fasteners.
  • Estimated Cost to Fix: $100 - $500+ depending on the severity and labor involved.
  • Recalls: None Found

Summary The 2021 Mercedes-Benz GLB35 AMG, while generally reliable, does have some common issues. The engine can experience coolant leaks and potentially high oil consumption. The transmission can have rough shifting and may need a software update or more significant repairs. Electrical issues with the MBUX infotainment system are also noted. Suspension and interior noise issues are less critical but can be bothersome. The cost of repairs can vary significantly, from relatively inexpensive fixes like software updates to more costly engine or transmission work. Overall, prospective buyers should be aware of these potential issues and inspect the vehicle thoroughly before purchasing.