2022 Chevrolet Silverado 2500HD Serpentine Belt Routing, Length & Part Numbers

As an ASE-certified master technician, I know that heavy-duty trucks like the 2022 Chevrolet Silverado 2500HD demand peak performance from every engine component. Whether your Silverado is equipped with the 6.6L L8T V8 Gas engine or the formidable 6.6L L5P Duramax V8 Diesel, the serpentine belt is the lifeline for your engine's accessories. It drives the alternator, water pump, power steering pump, and A/C compressor. When it snaps or slips, your truck is going nowhere.

Below is your comprehensive reference guide for the primary drive belt on the 2022 Chevrolet Silverado 2500HD (6.6L L5P Duramax Diesel - Single Alternator setup). Note: If you have dual alternators or the 6.6L Gas engine, belt lengths and part numbers will vary, so always verify with your VIN.

Quick answer

Here are the essential specifications and part numbers for the 2022 Silverado 2500HD 6.6L Duramax (single alternator) serpentine belt system:

• Belt Length: 121.3 inches (Effective Length)
• Rib Count: 6-rib
• OEM Belt PN: GM 12687339 (ACDelco 6K1213)
• Aftermarket Cross-References: Gates K061213, Dayco 5061213, Continental Elite 4061213
• Auto-Tensioner PN: GM 12675662 (ACDelco 38388)
• Idler Pulley PN: GM 12678505 (ACDelco 38018)

Belt routing

Pro-Tip: Always take a clear photograph of your existing belt routing with your smartphone before removing the old belt. It is the best reference you can have if you get lost.

Because we cannot render an image here, follow this text-based step-by-step description of the routing path for the standard 6.6L L5P configuration. Start from the bottom at the main drive pulley and work your way up and around:

1. Crankshaft Pulley: Start at the bottom center, wrapping the ribbed side of the belt around the bottom of the main crank pulley.
2. Water Pump: Bring the belt up and over the water pump pulley (ribbed side down).
3. Power Steering Pump: Route it down to the lower driver's side around the power steering pump.
4. Alternator: Bring the belt straight up to the top driver's side to wrap around the alternator.
5. Idler Pulley: Route the smooth backside of the belt under the upper idler pulley located near the center of the engine.
6. A/C Compressor: Pass the belt down to the passenger side, wrapping the ribbed side around the A/C compressor.
7. Auto-Tensioner: Finally, bring the smooth backside of the belt up and over the tensioner pulley. You will pull the tensioner to slip the final loop of the belt over the remaining smooth idler or back onto the alternator.

How to replace the serpentine belt

Replacing the belt on a 2500HD can be done in your driveway, though the tall ride height might require a step stool.

1. Locate the tensioner: The auto-tensioner is located on the front of the engine block. It features a square drive hole or a central bolt head designed for a tool.
2. Release the tension: Insert a dedicated serpentine belt tool or a long 3/8" drive breaker bar into the tensioner. Rotate the tensioner counter-clockwise (away from the belt) to relieve the spring pressure.
3. Remove the belt: Slide the old belt off the easiest to reach upper pulley (usually the alternator or upper idler) while holding the tensioner open. Carefully release the tensioner back to its resting position and pull the old belt out of the engine bay.
4. Route the new belt: Follow the routing path described above, leaving the easiest upper pulley for last.
5. Install the new belt: Compress the tensioner again using your breaker bar, slip the belt over the final pulley, and slowly release the tensioner.
6. Verify: Double-check that all belt ribs are perfectly seated inside the grooves of every ribbed pulley before starting the truck.

Replacement interval

For heavy-duty applications like the Silverado 2500HD, the serpentine belt should be inspected every 30,000 miles. A complete replacement of the belt, auto-tensioner, and idler pulleys is highly recommended between 60,000 and 100,000 miles, or roughly every 5 to 7 years. Because these trucks are often used for towing and hauling, the belt system experiences higher loads than standard passenger vehicles.

Signs of a failing belt or tensioner

Don't wait for the belt to snap on the highway. Watch out for these warning signs:

• Squealing or Chirping: High-pitched noises on startup or when accelerating indicate a slipping belt, a worn tensioner, or a misaligned pulley.
• Visible Wear: Look for deep cracks, missing chunks of ribs, or fraying edges on the belt.
• Tensioner Bounce: While the engine is idling, look at the auto-tensioner. If the arm is bouncing excessively, the internal spring or dampener has failed, and the tensioner must be replaced alongside the belt.
• Heavy Steering or Overheating: If the belt slips badly enough, your power steering will feel unusually heavy, and your engine coolant temperature may rise due to the water pump not spinning fast enough.

If you aren't comfortable doing this job yourself, or if you suspect your tensioner assembly has failed and requires more complex tear-down, don't risk a breakdown while towing. Find a trusted shop on Repairius.