Where to Find Serpentine Belt Routing Diagrams

You can usually find serpentine belt routing diagrams on the under‑hood belt routing sticker, in your vehicle’s owner’s manual, through the automaker’s official service information, or via reputable parts and repair databases. These sources provide the exact path the belt takes around pulleys and accessories, which is critical for proper fitment and operation.

The Most Reliable Places to Look

Several trusted sources consistently provide accurate belt routing information. The options below range from free labels and manuals to professional-grade databases that mirror dealership information.

• Under-hood routing label: Often located on the radiator support, underside of the hood, fan shroud, or near the belt/tensioner. It shows the precise pulley path for your engine configuration.
• Owner’s manual: Many manuals include a diagram or direct you to the correct section for belt routing and replacement procedures.
• Factory service information (OEM): Portals such as GM ACDelco TDS, Ford Motorcraft Service, Toyota TIS, Honda ServiceExpress, Stellantis TechAuthority (Chrysler/Dodge/Jeep/Ram), Nissan TechInfo, Subaru TechInfo, and Hyundai/Kia technical information sites provide definitive, VIN- and engine-specific diagrams.
• Aftermarket repair databases: ALLDATA (DIY or Pro), Mitchell 1 ProDemand, ChiltonDIY, and Haynes Online manuals carry OEM-derived diagrams with component notes and torque specs.
• Parts retailer repair guides: AutoZone’s Repair Help/Repair Guides, O’Reilly Auto Parts DIY resources, and NAPA/Advance Auto online guides often include belt routing by year/make/model/engine.
• Dealership parts/service departments: A parts counter or service advisor can print or email the correct diagram using your VIN.
• Service bulletins and technical diagrams: Some vehicles have TSBs with updated routing for revised tensioners or accessory deletes—these are in OEM portals and professional databases.

Using these sources helps ensure you get the correct diagram for your exact engine, accessory package (with or without A/C, power steering variants), and model year, reducing the risk of misrouting or belt squeal.

Step-by-Step: How to Find the Correct Diagram for Your Vehicle

If you don’t immediately see a diagram under the hood, follow this process to locate the right routing and confirm it matches your setup.

1. Gather identifiers: Note the VIN, model year, engine size/code, and whether the vehicle has A/C or other accessory changes.
2. Check the engine bay: Look for a belt routing sticker on the radiator support, fan shroud, or underside of the hood.
3. Consult the owner’s manual: Check the index for “drive belt,” “serpentine belt,” or “belt routing.”
4. Use the OEM service portal: Create a short-term subscription if needed and search by VIN for the drive belt diagram and procedure.
5. Try reputable retail repair guides: Enter your vehicle details on AutoZone/O’Reilly repair sections to view diagrams and component layouts.
6. Verify accessory configuration: Ensure the diagram matches your engine’s options (e.g., with/without A/C, secondary air pump, different alternator).
7. Cross-check part numbers: Match the belt length and rib count from the parts catalog to your diagram.
8. Document before removal: If replacing, photograph the existing belt routing from multiple angles.
9. Download/print the diagram: Keep it visible while routing the new belt.
10. Confirm tensioner location and rotation: The diagram should show the spring tensioner and the direction to relieve tension.
11. Final visual inspection: Ensure ribbed sides of the belt run on ribbed pulleys and the smooth side runs on smooth pulleys; verify full seating in grooves.

Following these steps helps ensure you obtain the exact routing and avoid common mistakes, especially on engines with multiple belt paths or accessory variants.

Free and Paid Options

Depending on how often you need service data and how detailed you want the information, you can choose between no-cost resources and professional-grade subscriptions.

• Free: Under-hood decal; owner’s manual (often free as a PDF on automaker sites); AutoZone Repair Guides and O’Reilly DIY resources with free accounts; community forum posts with verified diagrams.
• Paid: OEM service portals (day, month, or year subscriptions) with the most authoritative diagrams; ALLDATA DIY or Mitchell 1 for broader coverage across multiple brands; Haynes Online or ChiltonDIY for consumer-friendly manuals.

Free sources are often sufficient for a single repair, while paid platforms offer deeper procedures, torque specs, and bulletins for complex jobs or frequent use.

What If the Sticker Is Missing?

Missing or illegible stickers are common on older vehicles. Here are practical ways to proceed safely and accurately.

• Search alternate label locations: Some manufacturers place the decal on the timing cover or inner fender.
• Order a replacement decal: Dealers and some parts suppliers sell under-hood label replacements by VIN.
• Use OEM or retailer databases: Enter the VIN to pull the exact diagram for your engine and accessory setup.
• Create your own reference: Sketch or photograph the existing routing before you remove the old belt.
• Follow general routing rules cautiously: Ribbed side only on grooved pulleys; smooth pulleys are for the belt’s back. Identify the spring tensioner (often the only movable pulley).
• Beware of “near fit” belts: A slightly wrong length or routing can cause noise, charging issues, or belt walk-off.

With VIN-specific information and careful observation, you can confidently replace a missing sticker without risking misrouting.

Safety and Fitment Tips

Correct routing is only part of a successful belt service. These quick checks prevent common problems after installation.

• Work on a cool engine; keep hands clear of fans and moving pulleys.
• Use a serpentine belt tool or long-handled ratchet to relieve the tensioner safely.
• Inspect pulleys and bearings: Replace noisy idlers or a weak tensioner while you’re there.
• Confirm belt specs: Correct rib count and length for your exact accessory configuration.
• Align the belt in all grooves; recheck after a few minutes of engine run-in.
• Listen for chirps/squeals: Re-seat the belt, check pulley alignment, or replace worn components if noise persists.

These steps help ensure quiet operation, proper charging and cooling performance, and belt longevity.

Useful OEM and Retailer Portals

When you need authoritative diagrams or quick DIY references, these portals are the most commonly used by technicians and motorists alike.

• Automaker service sites: GM ACDelco TDS; Ford Motorcraft Service; Toyota TIS; Honda ServiceExpress; Stellantis TechAuthority (Chrysler/Dodge/Jeep/Ram); Nissan TechInfo; Subaru TechInfo; Hyundai and Kia technical information portals.
• Aftermarket databases: ALLDATA (DIY/Pro) and Mitchell 1 ProDemand for comprehensive OEM-sourced diagrams and procedures.
• Retailer guides: AutoZone Repair Help/Guides, O’Reilly DIY Center, and similar resources from NAPA/Advance Auto.

Start with the quickest free option available to you, then step up to OEM or professional databases if you need more detail or run into discrepancies.

Summary

Serpentine belt routing diagrams are found on the under-hood label, in the owner’s manual, within OEM service portals, and on trusted parts/repair databases. Use your VIN and engine details to ensure the diagram matches your vehicle’s exact accessory setup, and verify routing before starting the engine. When in doubt, consult OEM service information or a dealership for the most accurate, up-to-date diagram.

What else should be replaced when replacing a serpentine belt?

You can replace only the pulley, or you can buy a new tensioner with a new pulley attached, or you can buy a kit with a new belt, tensioner/pulley, and idler pulley if there is one, and do it all. The Armada’s belt looked absolutely fine with no cracks or dry rot, and the idler pulley was quiet.

Where can I find routing info for an engine drive belt?

Most vehicles nowadays usually have a belt routing sticker located somewhere in the engine compartment, making it even easier.

Where is the belt diagram located?

A: Commonly a belt routing diagram sticker is on the underside of the hood or in the engine compartment. If there is no diagram, make a sketch of the belt and pulleys before removing the belt. This will help you re-route the new belt correctly.

How do you find a serpentine belt routing diagram?

Look under the hood.
All vehicles come from the factory with the belt routing for that specific make and model under the hood. The diagram will show which pulleys each belt goes on and how to route the belt. Contact an expert on Dayco’s tech line at (800) 848-7902.