2015 Kenworth T680 Serpentine Belt Routing & Replacement Guide

Quick Answer

For your 2015 Kenworth T680, the serpentine belt system is crucial for operating many of your engine's accessories. Part numbers can vary significantly based on the specific engine (e.g., PACCAR MX-13, Cummins ISX15). Always verify with your VIN or a reputable parts supplier to ensure correct part identification.

• Belt Length: Varies by engine configuration. Typically in the range of 106-110 inches for most PACCAR MX-13 engines, but always verify.
• Rib Count: 8-rib (common for heavy-duty trucks)
• OEM Belt PN: Varies by engine. For PACCAR MX-13, common numbers include PACCAR 1934988R (example only, verify).
• Aftermarket Cross-references:
  • Gates K081060 (example for PACCAR MX-13, verify)
  • Dayco 5081060 (example for PACCAR MX-13, verify)
  • Continental Elite 4081060 (example for PACCAR MX-13, verify)
• Auto-Tensioner PN: Varies by engine. For PACCAR MX-13, common numbers include PACCAR 1934992 (example only, verify).
• Idler Pulley PN: Varies by engine. For PACCAR MX-13, common numbers include PACCAR 1934993 (example only, verify).

Belt Routing

Before you begin any work, it is highly recommended to take a clear photograph of the existing belt routing. This will serve as an invaluable reference during reinstallation.

The serpentine belt on your 2015 Kenworth T680 (with common PACCAR MX-13 engine configuration) typically follows a complex path that drives various accessories. Here is a general text-based description of a common routing path. Note: Exact routing can vary depending on engine options and specific accessory placement. Always consult your service manual or the diagram under the hood.

1. Begin at the Crankshaft Pulley, which is usually the largest pulley at the bottom front of the engine.
2. From the crankshaft, the belt typically routes up to the A/C Compressor Pulley.
3. Leaving the A/C compressor, the belt may then pass around an Idler Pulley (or multiple idlers) to guide it.
4. Next, the belt often routes to the Alternator Pulley.
5. From the alternator, it typically goes to the Power Steering Pump Pulley.
6. After the power steering pump, the belt will usually route to the Water Pump Pulley.
7. Finally, the belt will engage the Automatic Tensioner Pulley, which maintains the correct belt tension, before returning to the crankshaft pulley to complete the loop.

Remember to trace the path carefully from your reference photo or the under-hood diagram.

How to Replace the Serpentine Belt

Replacing the serpentine belt on a heavy-duty truck like the Kenworth T680 requires proper tools and caution.

1. Safety First: Ensure the engine is off and cool. Disconnect the battery to prevent accidental starting.
2. Locate the Tensioner: Identify the automatic belt tensioner. It will have a square opening (usually 3/8-inch or 1/2-inch) designed for a breaker bar or a specialized serpentine belt tool.
3. Relieve Tension: Insert your serpentine belt tool or a breaker bar into the tensioner