2007 GMC Sierra 2500 HD Classic

2007 GMC Sierra 2500 HD Classic

Overview

The 2007 GMC Sierra 2500 HD Classic, a robust heavy-duty pickup, is generally known for its durability, especially in its powertrain. This model year represents a continuation of a well-established platform, benefiting from years of refinement. While it’s built to handle demanding tasks, like any vehicle, it has specific areas that have seen more attention from owners regarding reliability. This analysis focuses on documented common issues beyond routine maintenance, providing insights into potential repair costs and solutions for owners of this capable truck.

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Engine

6.0L V8 Vortec (LQ4/LQ9)

Intake Manifold Gasket Leaks

• Symptoms: Coolant leaks, rough idle, potential overheating.
• Solution: Replacement of intake manifold gaskets.
• Cost: $300 - $600

Active Fuel Management (AFM) System Issues

• Symptoms: Engine misfires, oil consumption, ‘reduced engine power’ message.
• Solution: Deactivation of AFM or repair/replacement of lifters and related components.
• Cost: $1,500 - $3,000+

6.6L Duramax V8 (LLY/LBZ/LMM)

Glow Plug Issues

• Symptoms: Hard starting in cold weather, check engine light.
• Solution: Replacement of faulty glow plugs and potentially the glow plug module.
• Cost: $200 - $500

Injector Problems

• Symptoms: Rough idle, loss of power, black smoke, check engine light.
• Solution: Replacement of faulty fuel injectors.
• Cost: $1,000 - $2,500+

EGR Cooler Leaks

• Symptoms: Coolant loss, white smoke from exhaust, overheating.
• Solution: Replacement of the EGR cooler.
• Cost: $400 - $800

Transmission

4L80-E (4-Speed Automatic)

Torque Converter Issues

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

Allison 1000 (5-Speed Automatic)

Solenoid Pack Failure

• Symptoms: Harsh shifting, transmission slipping, failure to shift into certain gears.
• Solution: Replacement of the transmission solenoid pack.
• Cost: $500 - $1,000

Overheating (under heavy load)

• Symptoms: Transmission slipping, delayed shifts, potential damage.
• Solution: Transmission cooler upgrade or flush and filter replacement.
• Cost: $300 - $700

NV4500 (5-Speed Manual)

No widespread issues reported.

• Symptoms: N/A
• Solution: N/A
• Cost: Varies

Suspension

Standard Chassis

Ball Joint Wear

• Symptoms: Clunking noises, steering wander, uneven tire wear.
• Solution: Replacement of worn ball joints.
• Cost: $300 - $600

Leaf Spring Issues

• Symptoms: Sagging rear end, clunking over bumps, reduced load capacity.
• Solution: Replacement of broken or sagging leaf springs.
• Cost: $400 - $800

Electrical

General Electrical System

Alternator Failure

• Symptoms: Dimming lights, battery warning light, starting issues.
• Solution: Replacement of the alternator.
• Cost: $300 - $600

Body Control Module (BCM) Issues

• Symptoms: Intermittent electrical problems, malfunctioning lights, power windows, or door locks.
• Solution: Diagnosis and potential reprogramming or replacement of the BCM.
• Cost: $500 - $1,200

Exterior

Body Panels and Trim

Tailgate Latch Issues

• Symptoms: Difficulty opening or closing tailgate, rattling.
• Solution: Lubrication or replacement of tailgate latch mechanism.
• Cost: $100 - $300

Rust on Body Panels

• Symptoms: Visible rust, particularly around wheel wells, rocker panels, and cab corners.
• Solution: Rust repair and repainting, or replacement of affected panels.
• Cost: $500 - $2,000+

Interior

Interior Components

HVAC Blower Motor Failure

• Symptoms: No air conditioning or heat, or intermittent fan operation.
• Solution: Replacement of the blower motor and/or resistor.
• Cost: $200 - $400

Seat Wear

• Symptoms: Torn upholstery, worn seat bolsters (especially on driver’s seat).
• Solution: Seat cover replacement or professional upholstery repair.
• Cost: $200 - $600

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Summary Verdict

The 2007 GMC Sierra 2500 HD Classic is a workhorse with a generally strong reputation for reliability, particularly its heavy-duty engines and transmissions. The Duramax diesel and the 6.0L V8 are robust, though they can experience specific issues like injector problems or AFM system faults, respectively. The Allison 1000 transmission is also highly regarded, though occasional solenoid issues can arise. Common concerns outside the powertrain include suspension components like ball joints and leaf springs, as well as typical electrical issues such as alternator failure. Rust can be a concern on older models. Overall, with proper maintenance and addressing known issues, the Sierra 2500 HD Classic remains a capable and dependable truck for demanding tasks.