GMC Sierra 2500/3500 (2014-2019) Repair Manual

Engineered for power, towing, and demanding workloads, the GMC Sierra 2500 and 3500 (2014–2019) are built to perform under pressure. Keep your heavy-duty truck reliable with the Haynes Repair Manual—your trusted, step-by-step guide for maintenance and repairs tailored specifically to Sierra HD models.

Expert Guidance You Can Trust

Each Haynes manual is created from real-world teardown and rebuild experience. Inside, you'll find clear instructions, torque specifications, detailed illustrations, and professional repair tips that help you complete jobs confidently while avoiding costly dealership service fees.

Models & Engines Covered

• GMC Sierra 2500HD / 3500HD (2014–2019)
• 6.0L V8 Gasoline
• 6.6L V8 Turbo-Diesel Duramax (LML)

Common GMC Sierra 2500/3500 Issues (and How This Manual Helps)

• DEF & Emissions System Faults – Diagnosis, component replacement, and troubleshooting guidance, especially common around 70k miles.
• Turbocharger Wear on Duramax Engines – Step-by-step troubleshooting and rebuild procedures for issues that appear past 80k miles.
• Allison Transmission Problems – Includes fluid change intervals, fault code interpretation, and full servicing procedures.
• Front Suspension Wear – Detailed instructions for replacing tie rods, ball joints, bushings, and other steering components.
• Brake Rotor & Pad Wear – Replacement steps plus ABS diagnostic coverage.
• Cooling System Leaks – Water pump, radiator, and hose servicing to prevent overheating under load.

Driving Habits That Impact Maintenance

Frequent towing: Increases stress on brakes and turbocharger systems. The manual covers brake servicing, boost system diagnosis, and repairs to maintain towing power and safety.

Snow or rough terrain use: Accelerates wear on suspension components. Step-by-step suspension rebuild instructions are included.

High-mileage work use: Emphasizes the importance of transmission servicing and cooling system inspections. Full service intervals and troubleshooting charts are provided.

Older Sierra ownership: ABS sensor failures and timing chain issues become more common with age. Clear DIY instructions show how to fix these at home.

What’s Inside the Haynes Repair Manual

• Complete repair and maintenance procedures with factory torque specifications
• Maintenance schedules, service intervals, and fluid charts for Sierra HD engines
• Troubleshooting flowcharts for emissions, drivetrain, electrical, and cooling systems
• Covers brakes, suspension, steering, HVAC, bodywork, and wiring diagrams
• Hybrid format: printed manual plus easy-to-access online content

Full List of Vehicles Covered

• Make: GMC
• Model: Sierra 2500 HD, Sierra 3500 HD
• Year Range: 2014–2019

This manual's year range reflects the coverage available when the manual was written. The vehicle’s production years may extend beyond this range.

Engines Covered

• 6.0 CNG (LC8)
• 6.0 Gas (LC8)
• 6.0 Flex Fuel Gas (L96)
• 6.6 (Duramax) Diesel (L5P)
• 6.6 (Duramax) Diesel (LML)