The Alliant Power AP63632 is a new fuel rail pressure sensor for 2017–2023 GM L5P/L5D Duramax applications. Alliant’s Fuel Injection Fuel Rail Pressure Sensor monitors pressure in the fuel rail and communicates that information to the engine control system.

Features & Benefits

• New Alliant Power Fuel Rail Pressure Sensor (Alliant P/N AP63632)
• Fit, form, and function tested to meet or exceed original-equipment standards (per Alliant Power)
• Direct replacement for 12647909 / 12686809 / 6040509C91
• Backed by Alliant Power’s 24-month, unlimited-mileage warranty

Application

• Chevrolet Silverado 2500 HD / Silverado 3500 HD (2017–2023)
• GMC Sierra 2500 HD / Sierra 3500 HD (2017–2023)
• Chevrolet Silverado 4500 HD / Silverado 5500 HD / Silverado 6500 HD (2019–2022)
• Alliant Power lists additional vehicle applications for this part number

Always verify fitment against your VIN, engine, and OE part number before ordering.

Cross-Reference / Replaces

• General Motors: 12647909, 12686809
• Navistar: 6040509C91, 6040670C91, FT0424
• Alliant Power: AP63632

Warranty: Alliant Power’s standard warranty: 24 months with unlimited miles/hours on installed parts (Alliant Power warranty policy, rev. Aug 2025).