WAI 18500N Starter

Starter for medium-duty applications

This WAI starter, part number 18500N, is built for medium-duty trucks that need dependable cranking performance. It is a new, not remanufactured, unit with an offset gear reduction design and DENSO family architecture.

Key features

• 12V starter with 3.0 kW power rating
• Offset gear reduction design for efficient engagement
• Counterclockwise rotation with 11-tooth drive
• Flange mounting type for direct replacement applications
• 100% new construction using proprietary components and processes

Fitment and application details

Compatible with Chevrolet W4500 Tiltmaster and Chevrolet W5500 Tiltmaster applications, as well as GMC W4500 Forward, GMC W5500 Forward, GMC W5500HD Forward, and GMC W3500 Forward models. It also fits Isuzu NPR, NPR-HD, NRR, and NQR applications across the listed model years. For buyers searching for a Chevrolet W4500 Tiltmaster starter, GMC W5500 Forward starter, or Isuzu NPR starter, 18500N matches the specified DENSO OSGR configuration.

This part cross-references Davico Mfg 18500 for the same application.

What this starter is used for

• Restoring engine cranking when the original starter no longer engages reliably
• Replacing a worn unit with the correct 12V, 11-tooth, counterclockwise configuration
• Addressing slow or inconsistent starting caused by internal starter wear
• Matching DENSO OSGR applications that require flange-mounted fitment

Installation notes and tips

Verify the vehicle’s original starter specifications before installation, including voltage, rotation, tooth count, and mounting style. Confirm the application notes for DENSO OSGR fitment on Chevrolet, GMC, and Isuzu models to ensure the correct match for your truck.

Quality assurance

WAI states that this starter is engineered to deliver the amperage output needed for modern vehicles and is manufactured as a new unit rather than a remanufactured one.