2021 Chevrolet Silverado 6500 HD
The 2021 Chevrolet Silverado 6500 HD is a heavy-duty truck designed for demanding commercial applications. It offers a robust platform for various upfits and configurations. Engine options include the 6.6L Duramax diesel V8, producing 401 horsepower and 464 lb-ft of torque, and the 6.6L V8 gasoline engine, generating 401 horsepower and 464 lb-ft of torque. Both engines are commonly paired with a six-speed Allison transmission. Owners often praise the truck’s immense towing and payload capabilities, its relatively comfortable cabin for a work truck, and the strong performance of the Duramax diesel. However, some common dislikes include the vehicle’s large size making it difficult to maneuver in tight spaces, fuel economy, and higher price point compared to smaller trucks.
Engine
6.6L Duramax Diesel V8
- Fuel Injector Failure
- Description/Symptoms: Misfires, rough running, reduced power, excessive smoke (black or white) from the exhaust, and potential fuel dilution of the engine oil. Can trigger the check engine light.
- Solution: Diagnosis with a scan tool to identify the faulty injector(s). Replacement of the failed injector(s) is required, along with recalibration of the fuel system. Cleaning or flushing the fuel system may also be recommended.
- Estimated Cost to Fix: $800 - $1500+ per injector depending on location and shop rates.
- Recalls: None Found
- Diesel Particulate Filter (DPF) Issues
- Description/Symptoms: Frequent regeneration cycles, reduced fuel economy, clogged DPF leading to reduced power and potential engine damage. Warning lights may illuminate on the dashboard.
- Solution: Forced regeneration by a dealer or qualified mechanic, cleaning of the DPF, or replacement of the DPF if severely clogged or damaged. Address any underlying causes of excessive soot production, such as faulty injectors or turbocharger issues.
- Estimated Cost to Fix: DPF Cleaning $300 - $800, DPF Replacement $2000 - $4000+
- Recalls: None Found
6.6L V8 Gasoline
- Active Fuel Management (AFM) Lifter Failure
- Description/Symptoms: Misfires, rough running, “ticking” noise from the engine, reduced power, and check engine light. Caused by the AFM lifters collapsing.
- Solution: Replacement of the failed AFM lifters, and potentially the camshaft if damaged. Many owners opt to delete the AFM system entirely to prevent future issues.
- Estimated Cost to Fix: $3000 - $6000+ (AFM Delete tends to be at the higher end of the cost scale)
- Recalls: None Found
Transmission
Allison Six-Speed Automatic
- Torque Converter Failure
- Description/Symptoms: Slipping during acceleration, shuddering at highway speeds, difficulty shifting, abnormal noises from the transmission, and potential stalling.
- Solution: Replacement of the torque converter. Thoroughly flush the transmission cooler lines to remove debris.
- Estimated Cost to Fix: $2500 - $4500+
- Recalls: None Found
- Shift Solenoid Malfunction
- Description/Symptoms: Erratic shifting, harsh shifting, failure to shift into certain gears, transmission slipping, and check engine light.
- Solution: Diagnosis with a scan tool to identify the faulty solenoid(s). Replacement of the affected shift solenoid(s).
- Estimated Cost to Fix: $500 - $1500+ depending on the solenoid and shop rates.
- Recalls: None Found
Suspension
- Leaf Spring Sagging/Failure
- Description/Symptoms: Vehicle sagging on one or both sides, reduced load-carrying capacity, poor ride quality, and potential damage to other suspension components.
- Solution: Replacement of the leaf springs. Consider upgrading to heavier-duty springs if the vehicle is frequently used for heavy loads.
- Estimated Cost to Fix: $800 - $2000+ per side depending on the spring type and shop rates.
- Recalls: None Found
- Front End Component Wear (Ball Joints, Tie Rods)
- Description/Symptoms: Loose steering, clunking noises from the front end, uneven tire wear, and difficulty maintaining alignment.
- Solution: Inspection of the front end components. Replacement of worn or damaged ball joints, tie rod ends, and potentially other steering components.
- Estimated Cost to Fix: $500 - $2000+ depending on the components needing replacement and shop rates.
- Recalls: None Found
Electrical
- Body Control Module (BCM) Issues
- Description/Symptoms: Intermittent electrical problems affecting various systems, such as lights, power windows, door locks, and radio. Can cause false warnings or malfunctions.
- Solution: Diagnosis with a scan tool to confirm BCM failure. Reprogramming or replacement of the BCM may be required.
- Estimated Cost to Fix: $500 - $1500+ depending on programming and shop rates.
- Recalls: None Found
- Sensor Failures (ABS, TPMS, etc.)
- Description/Symptoms: Warning lights illuminating on the dashboard, malfunctioning systems (ABS, TPMS, etc.), and potential performance issues.
- Solution: Diagnosis with a scan tool to identify the faulty sensor. Replacement of the failed sensor.
- Estimated Cost to Fix: $150 - $500+ per sensor depending on the type and shop rates.
- Recalls: None Found
Exterior
- Rust in cab corner areas
- Description/Symptoms: Rust appearing in the cab corners, especially in environments where road salt is used.
- Solution: Repair the affected area by cutting out the rust, welding in a new patch, and repainting the area.
- Estimated Cost to Fix: $500 - $2000+ per side depending on the severity of the rust and shop rates.
- Recalls: None Found
Interior
- Infotainment System Freezing/Crashing
- Description/Symptoms: The infotainment screen freezing, crashing, or becoming unresponsive. Can affect radio, navigation, and other vehicle functions.
- Solution: Software update (if available), or replacement of the infotainment system module.
- Estimated Cost to Fix: $200 - $1500+ depending on repair/replacement required
- Recalls: None Found
Summary
The 2021 Chevrolet Silverado 6500 HD is generally a reliable work truck but is subject to some common issues. Engine problems, particularly related to fuel injectors on the Duramax diesel and AFM lifters on the gasoline V8, can be costly to repair. Transmission issues, such as torque converter failure, are also a concern. Electrical problems can be intermittent and difficult to diagnose. Overall, potential buyers should be aware of these potential issues and factor in potential repair costs when considering this truck. The severity of the issues ranges from minor inconveniences to major mechanical failures. Costs to address these problems can range from a few hundred dollars for sensor replacements to several thousand dollars for engine or transmission repairs.