WAI 31257N Starter

Starter for Mercedes-Benz and INFINITI Applications

WAI 31257N is a 12-volt starter built with a permanent magnet gear reduction design and a 1.7 kW power rating. It is a 100% new unit, not remanufactured, and is engineered for the amp output needed in modern vehicles.

• 12-volt starter for charging and starting system repair
• Permanent magnet gear reduction design for efficient cranking performance
• 1.7 kW power rating
• Clockwise (right) rotation
• 13-tooth drive gear
• Flange mounting type
• DENSO family starter configuration

Detailed Product Overview

This WAI starter, part number 31257N, is built for direct replacement use on select Mercedes-Benz and INFINITI vehicles. It matches DENSO PMGR 13-tooth applications and is listed for models including Mercedes-Benz C300, E300, GLC300, GLC350e, SLC300, C350e, Metris, Sprinter 1500, and Sprinter 2500, along with INFINITI Q50 and Q60 coverage. The 12-volt electrical setup, clockwise rotation, and flange mount design support proper fitment where the original starter uses the same configuration.

This part cross-references Mercedes-Benz OE numbers 274 906 04 00 and 274-906-21-00 for the same application.

What This Starter Helps Address

• No-crank or intermittent crank conditions
• Slow engine cranking during startup
• Starter noise from worn internal components
• Electrical starting failure on DENSO PMGR applications
• Replacement needs for a failed OE-style starter on Mercedes-Benz and INFINITI vehicles

Installation Notes and Tips

Verify the original starter’s rotation, tooth count, mounting style, and electrical specification before installation. Confirm vehicle fitment by year, make, model, and engine application, especially on Mercedes-Benz C300, E300, GLC300, GLC350e, SLC300, Metris, and Sprinter platforms. Compare the OE part number and connector layout to the removed unit to ensure correct replacement.

Quality Assurance

WAI starters are manufactured as new components using proprietary processes and parts selection aimed at consistent performance and service life. Part number 31257N is built to meet the demands of modern starting systems with a new-unit construction.