2008 GMC Sierra 2500 HD

The 2008 GMC Sierra 2500 HD is a popular heavy-duty truck known for its towing capacity and durability. Engine options included the 6.0L Vortec V8 (353 hp and 373 lb-ft of torque), the 8.1L Vortec V8 (325 hp and 447 lb-ft of torque), and the 6.6L Duramax Turbo Diesel V8 (365 hp and 660 lb-ft of torque). Transmission choices were either a 6-speed manual or a 6-speed Allison automatic. Owners often praise the Sierra 2500 HD for its workhorse capabilities, comfortable ride (for a heavy-duty truck), and relatively simple maintenance. Common complaints include fuel economy (especially with the gas engines), some electrical gremlins, and the overall size making it difficult to maneuver in tight spaces.

Engine

6.0L Vortec V8

• Oil Consumption
  • Description/Symptoms: Excessive oil consumption, sometimes leading to engine damage if not monitored. Blue smoke from the exhaust is a common symptom.
  • Solution: Potential solutions range from replacing valve stem seals to piston ring replacement, or ultimately, a full engine rebuild.
  • Estimated Cost to Fix: $500 - $5,000+, depending on the severity and chosen repair.
  • Recalls: None Found
• Exhaust Manifold Bolts
  • Description/Symptoms: Broken exhaust manifold bolts, resulting in exhaust leaks and a ticking noise, especially noticeable upon startup.
  • Solution: Removal of broken bolts (often requiring specialized tools or welding) and replacement with new bolts and gaskets.
  • Estimated Cost to Fix: $300 - $800, depending on the number of broken bolts and labor rates.
  • Recalls: None Found

6.6L Duramax Turbo Diesel V8 (LLY/LBZ)

• Fuel Injector Failure
  • Description/Symptoms: Rough running engine, misfires, decreased fuel economy, and black smoke from the exhaust. Diagnostic Trouble Codes (DTCs) related to fuel injector performance are common.
  • Solution: Replacement of faulty fuel injectors. It is generally recommended to replace all injectors at once for even wear and performance.
  • Estimated Cost to Fix: $2,000 - $4,000+, depending on the shop and parts used.
  • Recalls: None Found
• Turbocharger Failure
  • Description/Symptoms: Loss of power, excessive black smoke, whining noises from the turbocharger, and potentially Diagnostic Trouble Codes (DTCs) related to turbocharger performance.
  • Solution: Replacement or rebuild of the turbocharger.
  • Estimated Cost to Fix: $1,500 - $3,500+, depending on whether a new or rebuilt unit is used.
  • Recalls: None Found
• Head Gasket Failure (LLY)
  • Description/Symptoms: Overheating, coolant loss, white smoke from exhaust, and coolant mixing with oil.
  • Solution: Replacement of the head gaskets. This is a labor-intensive job often including machining of the cylinder heads.
  • Estimated Cost to Fix: $3,000 - $6,000+
  • Recalls: None Found

8.1L Vortec V8

• No Issues Found

Transmission

Allison 1000 6-Speed Automatic

• Torque Converter Failure
  • Description/Symptoms: Shuddering during shifts, especially at lower speeds, slipping, and potential stalling.
  • Solution: Replacement of the torque converter.
  • Estimated Cost to Fix: $800 - $2,000, depending on the shop and parts used.
  • Recalls: None Found
• Valve Body Issues
  • Description/Symptoms: Hard or erratic shifting, delayed engagement, and slipping.
  • Solution: Replacement or rebuild of the valve body.
  • Estimated Cost to Fix: $500 - $1,500
  • Recalls: None Found

ZF S6-650 6-Speed Manual

• No Issues Found

Suspension

• Leaf Spring Sag
  • Description/Symptoms: Rear of the truck sagging, reduced load-carrying capacity, and potentially a rougher ride.
  • Solution: Replacement of the leaf springs or adding helper springs.
  • Estimated Cost to Fix: $400 - $1,500
  • Recalls: None Found
• Front End Component Wear
  • Description/Symptoms: Loose steering, wandering, and uneven tire wear. Common culprits are ball joints, tie rod ends, and idler arms.
  • Solution: Replacement of worn front end components.
  • Estimated Cost to Fix: $300 - $1,200
  • Recalls: None Found

Electrical

• Body Control Module (BCM) Issues
  • Description/Symptoms: Intermittent electrical problems, such as malfunctioning power windows, door locks, or lights.
  • Solution: Replacement or reprogramming of the BCM.
  • Estimated Cost to Fix: $300 - $800+
  • Recalls: None Found
• Fuel Gauge Inaccuracy
  • Description/Symptoms: Inaccurate fuel gauge readings, leading to potential running out of fuel unexpectedly.
  • Solution: Replacement of the fuel level sensor in the fuel tank.
  • Estimated Cost to Fix: $200 - $500
  • Recalls: None Found

Exterior

• Rust on Rocker Panels and Cab Corners
  • Description/Symptoms: Rust formation on the rocker panels and cab corners, especially in areas with harsh winters and road salt.
  • Solution: Rust repair, including cutting out rusted metal, welding in new metal, and painting.
  • Estimated Cost to Fix: $500 - $2,000+
  • Recalls: None Found

Interior

• Dashboard Cracking
  • Description/Symptoms: Cracking of the dashboard, especially in hot climates.
  • Solution: Replacement of the dashboard or installation of a dashboard cover.
  • Estimated Cost to Fix: $300 - $1,500
  • Recalls: None Found

Summary

The 2008 GMC Sierra 2500 HD can be a reliable workhorse, but potential buyers should be aware of the common issues. The Duramax diesel, while powerful, can suffer from expensive fuel injector and turbocharger issues. The 6.0L gas engine can consume oil. Electrical gremlins stemming from the BCM are another potential headache. Rust is a concern in certain climates. Overall, the severity and cost of repairs can range from relatively minor to significant, so a thorough inspection is recommended before purchasing.