2015 GMC Sierra
The 2015 GMC Sierra 1500 is a popular full-size pickup truck known for its comfortable ride, strong towing capabilities, and refined interior. Engine options included a 4.3L EcoTec3 V6 (285 hp and 305 lb-ft of torque), a 5.3L EcoTec3 V8 (355 hp and 383 lb-ft of torque), and a 6.2L EcoTec3 V8 (420 hp and 460 lb-ft of torque). Transmission options were primarily a 6-speed automatic, although some later 2015 models with the 6.2L engine were equipped with an 8-speed automatic. Owners generally appreciate the Sierra’s comfortable cabin and powerful engine options. Common complaints include transmission issues (especially with the 8-speed), electronic glitches, and some concerns about the reliability of certain engine components.
Engine
4.3L EcoTec3 V6
- No Issues Found
5.3L EcoTec3 V8
- Active Fuel Management (AFM) Lifter Failure
- Description/Symptoms: Misfires, rough idling, and engine knocking are common symptoms. This is due to AFM lifters collapsing. Often accompanied by a check engine light.
- Solution: Replacing the failed lifters is the standard repair, often including replacing all lifters and potentially the camshaft if damaged. Some owners opt to delete the AFM system entirely to prevent future issues.
- Estimated Cost to Fix: $2,000 - $4,000+
- Recalls: None Found
- Excessive Oil Consumption
- Description/Symptoms: Low oil level, needing to add oil frequently between oil changes. Blue smoke from the exhaust pipe indicates burning oil.
- Solution: GM issued a technical service bulletin (TSB) #16-NA-014 to address this issue, which involves revised valve cover and oil deflector designs. More severe cases may require piston ring replacement.
- Estimated Cost to Fix: $500 - $3,000+ depending on the severity and repair method.
- Recalls: None Found
6.2L EcoTec3 V8
- Active Fuel Management (AFM) Lifter Failure
- Description/Symptoms: Misfires, rough idling, and engine knocking are common symptoms. This is due to AFM lifters collapsing. Often accompanied by a check engine light.
- Solution: Replacing the failed lifters is the standard repair, often including replacing all lifters and potentially the camshaft if damaged. Some owners opt to delete the AFM system entirely to prevent future issues.
- Estimated Cost to Fix: $2,000 - $4,000+
- Recalls: None Found
- Excessive Oil Consumption
- Description/Symptoms: Low oil level, needing to add oil frequently between oil changes. Blue smoke from the exhaust pipe indicates burning oil.
- Solution: GM issued a technical service bulletin (TSB) #16-NA-014 to address this issue, which involves revised valve cover and oil deflector designs. More severe cases may require piston ring replacement.
- Estimated Cost to Fix: $500 - $3,000+ depending on the severity and repair method.
- Recalls: None Found
Transmission
6-Speed Automatic (6L80)
- Torque Converter Shudder
- Description/Symptoms: A noticeable shudder or vibration at lower speeds, particularly when the torque converter is locking up.
- Solution: Replacing the torque converter or performing a transmission flush with a specific fluid designed to address shudder can resolve the issue.
- Estimated Cost to Fix: $500 - $2,000
- Recalls: None Found
8-Speed Automatic (8L90)
- Rough Shifting/Hesitation
- Description/Symptoms: Harsh or erratic shifting, hesitation between gears, and clunking noises during gear changes.
- Solution: Software recalibration is often the first step. If that doesn’t work, replacement of valve body components or, in severe cases, the entire transmission is necessary. GM released multiple TSBs to address this issue including replacing the torque converter and using an updated transmission fluid.
- Estimated Cost to Fix: $100 - $5,000+ depending on the severity and the repair needed
- Recalls: None Found
Suspension
- Premature Wear of Shocks/Struts
- Description/Symptoms: Bouncy ride, excessive body roll when cornering, and clunking noises from the suspension.
- Solution: Replacing the worn shocks and/or struts.
- Estimated Cost to Fix: $300 - $1,000+
- Recalls: None Found
Electrical
- Infotainment System Glitches
- Description/Symptoms: Freezing, slow response, Bluetooth connectivity problems, and screen malfunctions with the MyLink system.
- Solution: Software updates from the dealer. In some cases, replacing the infotainment system module is required.
- Estimated Cost to Fix: $0 (software update) - $1,200+ (module replacement)
- Recalls: None Found
- Battery Drain
- Description/Symptoms: The battery dies overnight or after the vehicle sits for a short period.
- Solution: Identifying the parasitic draw (the component that is draining the battery when the vehicle is off) and repairing or replacing it. Common culprits include the infotainment system, OnStar module, or a faulty relay.
- Estimated Cost to Fix: $100 - $500+
- Recalls: None Found
Exterior
- Poor Quality Chrome Trim
- Description/Symptoms: Chrome trim pieces (bumpers, grille, etc.) peeling, bubbling, or corroding.
- Solution: Replacement of the affected trim pieces.
- Estimated Cost to Fix: $100 - $1,000+ depending on the piece and if you replace it with an OEM or aftermarket part.
- Recalls: None Found
Interior
- Cracked Dashboard
- Description/Symptoms: Cracks appearing on the dashboard, especially in hot climates.
- Solution: Replacing the dashboard or using a dashboard cover.
- Estimated Cost to Fix: $200 - $1,500+
- Recalls: None Found
Summary
The 2015 GMC Sierra 1500 is a capable truck with some notable issues. The most significant and potentially costly problems revolve around the Active Fuel Management (AFM) system and excessive oil consumption on the 5.3L and 6.2L V8 engines, and the shifting issues with the 8-speed automatic transmission (8L90). Electrical glitches and exterior trim issues are also common, though less severe. Potential buyers should carefully inspect the vehicle for signs of these problems and inquire about any relevant repairs or maintenance history. Addressing these issues can range from a few hundred dollars for minor repairs to several thousand dollars for major engine or transmission work.