2009 GMC T6500

Here’s a comprehensive breakdown of common issues and complaints reported for the 2009 GMC T6500, categorized by component. This medium-duty truck was available with several engine and transmission options, including the Duramax diesel engines and Allison transmissions. Owners generally appreciate the truck’s durability and workhorse capabilities but sometimes cite concerns about maintenance costs and the complexity of diesel emissions systems.

Engine

Duramax 6.6L Diesel (LLY/LBZ)

• Fuel Injector Failure
  • Description/Symptoms: Rough running, misfires, white smoke from exhaust, decreased fuel economy. Injectors can fail due to contamination or wear.
  • Solution: Replace faulty fuel injectors. It’s often recommended to replace all injectors at once to ensure even performance and prevent future issues.
  • Estimated Cost to Fix: $2,000 - $4,000+ (depending on the number of injectors replaced and shop labor rates)
  • Recalls: None Found
• Turbocharger Failure
  • Description/Symptoms: Loss of power, black smoke from exhaust, whistling or grinding noises from the turbocharger, potential oil leaks.
  • Solution: Replace the turbocharger. Inspect oil lines and air intake system for any obstructions or damage.
  • Estimated Cost to Fix: $1,500 - $3,500+ (depending on turbocharger model and labor rates)
  • Recalls: None Found
• EGR Cooler Leaks
  • Description/Symptoms: Coolant loss, white smoke from exhaust, engine overheating. The EGR (Exhaust Gas Recirculation) cooler can develop leaks due to thermal stress and corrosion.
  • Solution: Replace the EGR cooler. Inspect EGR valve and related components for excessive carbon buildup.
  • Estimated Cost to Fix: $800 - $2,000+
  • Recalls: None Found
• Glow Plug Issues
  • Description/Symptoms: Hard starting, especially in cold weather, excessive white smoke at start-up.
  • Solution: Replace faulty glow plugs. Also, test and replace the glow plug controller if needed.
  • Estimated Cost to Fix: $300 - $800+
  • Recalls: None Found

8.1L Vortec Gasoline Engine

• Exhaust Manifold Leaks
  • Description/Symptoms: Ticking or hissing noise, especially when the engine is cold, reduced fuel economy, potential exhaust smell in the cabin.
  • Solution: Replace the exhaust manifold and gasket. Use updated manifold designs to prevent future warping.
  • Estimated Cost to Fix: $500 - $1,200+
  • Recalls: None Found
• Oil Consumption
  • Description/Symptoms: Low oil levels, blue smoke from exhaust, need to add oil frequently.
  • Solution: Depending on the severity, the solution could range from using a thicker oil and monitoring oil levels to a complete engine rebuild.
  • Estimated Cost to Fix: $100 for oil changes to $5,000+ for engine work
  • Recalls: None Found

Transmission

Allison 1000/2000 Series Transmissions

• Torque Converter Issues
  • Description/Symptoms: Shuddering, slipping, or stalling, especially under load.
  • Solution: Replace the torque converter. Inspect the transmission fluid for debris, which could indicate internal damage.
  • Estimated Cost to Fix: $1,500 - $3,500+
  • Recalls: None Found
• Shift Solenoid Failure
  • Description/Symptoms: Erratic shifting, hard shifts, or failure to shift into certain gears.
  • Solution: Replace faulty shift solenoids. Consider replacing the transmission fluid and filter at the same time.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found
• Valve Body Issues
  • Description/Symptoms: Delayed engagement, harsh or soft shifts, slipping.
  • Solution: Replace or rebuild the valve body.
  • Estimated Cost to Fix: $800 - $2,500+
  • Recalls: None Found
• Internal Seal Leaks
  • Description/Symptoms: Transmission fluid leaks, slipping, difficulty shifting.
  • Solution: Drop transmission and replace the internal seals.
  • Estimated Cost to Fix: $800 - $2,000+
  • Recalls: None Found

Suspension

• Worn Ball Joints and Tie Rod Ends
  • Description/Symptoms: Loose steering, clunking noises from the front end, uneven tire wear.
  • Solution: Replace worn ball joints and tie rod ends. Get a wheel alignment after replacement.
  • Estimated Cost to Fix: $400 - $1,000+ per axle
  • Recalls: None Found
• Leaf Spring Sagging/Cracking
  • Description/Symptoms: Reduced ride height, poor ride quality, cracking in leaf springs.
  • Solution: Replace or add-a-leaf to the leaf spring pack.
  • Estimated Cost to Fix: $500 - $1,500+ per axle
  • Recalls: None Found

Electrical

• Wiring Harness Issues
  • Description/Symptoms: Intermittent electrical problems, such as lights flickering, gauges not working, or starting issues.
  • Solution: Inspect and repair damaged wiring harnesses. Look for chafing or corrosion.
  • Estimated Cost to Fix: $200 - $1,000+ (depending on the extent of the damage)
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Battery dies overnight or after short periods of inactivity.
  • Solution: Diagnose and repair parasitic drain. Check for aftermarket accessories, faulty relays, or other electrical components drawing power.
  • Estimated Cost to Fix: $100 - $500+ (depending on the source of the drain)
  • Recalls: None Found

Exterior

• Rust on Frame and Body Panels
  • Description/Symptoms: Rust forming on the frame, rocker panels, and other body panels, especially in areas exposed to road salt.
  • Solution: Remove rust, repair damaged metal, and repaint. Apply rust inhibitor coatings.
  • Estimated Cost to Fix: Varies greatly depending on severity, from $200 for minor spot repairs to $5,000+ for extensive rust repair.
  • Recalls: None Found

Interior

• HVAC Blower Motor Failure
  • Description/Symptoms: Blower motor not working or only working on certain speeds.
  • Solution: Replace the blower motor and blower motor resistor.
  • Estimated Cost to Fix: $200 - $500+
  • Recalls: None Found

Summary

The 2009 GMC T6500, like many medium-duty trucks, can present a range of issues, primarily related to the diesel engine (if equipped) and transmission. Fuel injector issues, turbocharger failures, and EGR cooler leaks can be costly. Suspension components like ball joints and leaf springs wear out over time. Electrical gremlins, such as wiring harness problems and battery drains, can also occur. The severity and cost of these issues vary greatly, but owners should be prepared for potential repairs, especially on higher-mileage vehicles. Rust is also a significant concern, particularly in regions with harsh winter conditions.