2007 GMC Sierra 2500 HD

2007 GMC Sierra 2500 HD

Overview

The 2007 GMC Sierra 2500 HD is a heavy-duty pickup truck known for its robust construction and towing capabilities. As a model from the GMT900 generation, it generally offers good reliability, especially for its intended purpose. However, like any vehicle, certain components and systems can experience issues over time. This analysis focuses on documented, non-wear-and-tear related problems reported by owners and technicians, covering key areas such as the powertrain, suspension, electrical systems, and interior/exterior components. Understanding these potential weak points can help owners with maintenance and repair planning.

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Engine

6.0L V8 Vortec (LQ4/LQ9)

Intake Manifold Gasket Leaks

• Symptoms: Coolant leaks, rough idle, potential engine overheating.
• Solution: Replacement of intake manifold gaskets.
• Cost: $400 - $700

Active Fuel Management (AFM) lifter issues

• Symptoms: Engine misfires, ticking noise from the engine, reduced power, check engine light.
• Solution: Replacement of lifters, camshaft, and potentially oil pump. Deactivation of AFM system is also an option.
• Cost: $1,500 - $3,000+

6.6L V8 Duramax Diesel (LLY/LBZ/LMM)

Glow Plug Issues

• Symptoms: Hard starting in cold weather, check engine light, rough idle.
• Solution: Replacement of faulty glow plugs and potentially glow plug control module.
• Cost: $300 - $600

Injector Problems

• Symptoms: Rough idle, loss of power, black smoke, check engine light.
• Solution: Replacement of faulty fuel injectors.
• Cost: $1,200 - $2,500+

EGR System Issues

• Symptoms: Reduced engine performance, black smoke, check engine light.
• Solution: Cleaning or replacement of Exhaust Gas Recirculation (EGR) valve and cooler.
• Cost: $500 - $1,000

Transmission

4L80-E (4-Speed Automatic)

Torque Converter Issues

• Symptoms: Slipping, shuddering, delayed engagement, fluid leaks.
• Solution: Rebuild or replacement of the torque converter.
• Cost: $800 - $1,500

Allison 1000 (5-Speed Automatic)

Torque Converter Clutch (TCC) Slipping

• Symptoms: Shuddering during acceleration, slipping gears, check engine light.
• Solution: Replacement of the torque converter and potentially transmission fluid and filter.
• Cost: $1,000 - $2,000

Transmission Fluid Leaks

• Symptoms: Visible fluid leaks, low transmission fluid level, shifting problems.
• Solution: Inspection and repair of seals, gaskets, or cooler lines.
• Cost: $300 - $700

Suspension

Standard Chassis

Ball Joint Wear

• Symptoms: Clunking noises over bumps, steering wander, uneven tire wear.
• Solution: Replacement of worn ball joints.
• Cost: $400 - $800

Leaf Spring Issues

• Symptoms: Sagging rear end, clunking noises, reduced load capacity.
• Solution: Replacement of broken or sagging leaf springs.
• Cost: $500 - $1,000

Electrical

Body Control Module (BCM)

Intermittent Electrical Failures

• Symptoms: Malfunctioning power windows, locks, lights, or dashboard indicators.
• Solution: Diagnosis and reprogramming or replacement of the BCM.
• Cost: $500 - $1,000

Alternator

Alternator Failure

• Symptoms: Dimming headlights, battery warning light, dead battery.
• Solution: Replacement of the alternator.
• Cost: $400 - $700

Exterior

Tailgate Latches

Sticking Tailgate Latches

• Symptoms: Difficulty opening or closing the tailgate.
• Solution: Lubrication or replacement of tailgate latch mechanisms.
• Cost: $150 - $300

Headlight Lens Hazing

Hazing/Yellowing Headlight Lenses

• Symptoms: Reduced headlight visibility, aesthetic degradation.
• Solution: Restoration kits or replacement of headlight assemblies.
• Cost: $100 - $400

Interior

HVAC Blower Motor

HVAC Blower Motor Failure

• Symptoms: No air coming from vents or intermittent airflow.
• Solution: Replacement of the blower motor and resistor.
• Cost: $200 - $400

Seat Heater Elements

Non-functional Seat Heaters

• Symptoms: Heated seats do not warm up.
• Solution: Replacement of the seat heater elements or associated wiring.
• Cost: $300 - $600

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Summary Verdict

The 2007 GMC Sierra 2500 HD is a capable and generally reliable heavy-duty truck. The Duramax diesel engine, while powerful, can be prone to issues with glow plugs, injectors, and the EGR system, which are common for diesel powertrains of this era. The gasoline V8 has potential for intake manifold leaks and AFM-related problems. Transmission issues, particularly with the Allison 1000, often involve the torque converter. Suspension components like ball joints and leaf springs can wear over time, especially under heavy use. Electrical gremlins, such as BCM issues and alternator failures, can occur. Interior and exterior components are less prone to major failures, with common issues being HVAC blower motors and tailgate latches. Overall, with proper maintenance and addressing known issues, the 2007 Sierra 2500 HD can remain a dependable workhorse.