2021 GMC Sierra

2021 GMC Sierra

The 2021 GMC Sierra is a full-size pickup truck that offers a wide range of engine and transmission options. It is available with four engine options: a 4.3L V6, a 5.3L V8, a 6.2L V8, and a 3.0L Duramax turbo-diesel V6. Transmission options include a 6-speed automatic, an 8-speed automatic, and a 10-speed automatic.

The Sierra is a popular choice for truck buyers due to its spacious interior, powerful engines, and impressive towing and payload capacities. However, some owners have reported experiencing issues with the vehicle.

Engine

4.3L V6

• AFM lifter failure: The Active Fuel Management (AFM) system can cause the lifters to fail, resulting in a loss of power and a knocking noise.
  • Solution: Replace the lifters.
  • Estimated Cost to Fix: $1,500 - $2,500+
  • Recalls: None Found

5.3L V8

• AFM lifter failure: The Active Fuel Management (AFM) system can cause the lifters to fail, resulting in a loss of power and a knocking noise.
  • Solution: Replace the lifters.
  • Estimated Cost to Fix: $1,500 - $2,500+
  • Recalls: None Found

6.2L V8

• No Issues Found

3.0L Duramax Turbo-Diesel V6

• Injector failure: The fuel injectors can fail, causing poor engine performance and a loss of power.
  • Solution: Replace the injectors.
  • Estimated Cost to Fix: $1,000 - $2,000+
  • Recalls: None Found

Transmission

6-Speed Automatic

• Shifting problems: The transmission may experience difficulty shifting gears, causing a loss of power and a rough ride.
  • Solution: Replace the transmission.
  • Estimated Cost to Fix: $4,000 - $6,000+
  • Recalls: None Found

8-Speed Automatic

• No Issues Found

10-Speed Automatic

• Shift flare: The transmission may hesitate or flare when shifting gears, causing a loss of power and a rough ride.
  • Solution: Update the transmission software.
  • Estimated Cost to Fix: None (covered under warranty)
  • Recalls: None Found

Suspension

• Rear suspension clunking: The rear suspension can make a clunking noise when driving over bumps.
  • Solution: Replace the rear suspension components.
  • Estimated Cost to Fix: $500 - $1,000+
  • Recalls: None Found

Electrical

• Battery drain: The battery can drain prematurely due to a faulty alternator or a parasitic drain.
  • Solution: Replace the alternator or identify and fix the parasitic drain.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found

Exterior

• Rust issues: The body of the truck can develop rust spots, especially around the rear wheel wells.
  • Solution: Apply rust-resistant coatings and keep the truck clean.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found

Interior

• Steering wheel peeling: The steering wheel can peel or crack over time.
  • Solution: Replace the steering wheel.
  • Estimated Cost to Fix: $500 - $1,000+
  • Recalls: None Found

Summary

The 2021 GMC Sierra is a popular truck with some severe and costly issues reported. Some of the most common issues include AFM lifter failure, injector failure, shifting problems, rear suspension clunking, battery drain, and rust issues. The severity and cost of these issues can vary, but it is important to be aware of them before purchasing or owning a Sierra.