GM GENUINE PARTS Fuel Tank Filler Cap GT347 (20962524) — Threaded OEM Fit with Rubber Gasket

The GM Genuine Parts GT347 (20962524) Fuel Tank Filler Cap is an original-equipment threaded fuel cap that seals the filler neck to retain fuel and keep contaminants out.

This replacement fuel tank filler cap is built to the same specifications as the factory-installed part for compatible GM vehicles. It uses a molded rubber gasket and precision threads to form a secure, liquid-tight closure for the fuel filler, helping protect the tank from water, dust, and fuel loss while maintaining the vehicle’s designed evaporative system performance.

How does this cap secure my fuel and reduce contamination?

The GT347 fastens with matching threads and a resilient rubber seal to close the filler neck tightly. That physical barrier keeps liquid fuel inside while barring entry of dirt, rain, and road grime that could otherwise enter the tank.

• Molded rubber gasket for a reliable liquid-tight seal
• Threaded design ensures consistent mechanical engagement
• Prevents debris and moisture from reaching the fuel

Will this cap work with my GM vehicle and the evaporative system?

This cap is manufactured as a GM-recommended replacement and matches original equipment dimensions for compatible models. Some versions include a one-way or pressure-relief check function to equalize tank pressure while maintaining proper sealing for the evaporative emissions system.

• OEM fitment for vehicles that require part number 20962524 / GT347
• Check-valve design on applicable units to manage tank pressure
• Meets General Motors’ original component specifications

How does a proper fuel cap help with running costs and emissions?

A correctly installed, tight-fitting fuel cap reduces vapor losses and helps prevent fuel evaporation, which can lower the amount of fuel you lose between fill-ups. By keeping vapors contained, it also supports the vehicle’s emission-control systems and helps limit unnecessary evaporative emissions.

• Reduces vapor escape that can waste fuel
• Supports the vehicle’s evaporative emissions control strategy
• Helps maintain predictable fuel economy and fewer refueling stops

How durable is the GM Genuine Parts filler cap and what maintenance does it need?

Constructed to GM OEM standards, this cap is designed for long service life under normal driving conditions. Routine inspection of the gasket and threads for wear, cracking, or contamination will help ensure continued sealing performance.

• Built to GM quality and durability standards
• Inspect rubber gasket periodically for cracks or hardening
• Clean threads and seat area to preserve proper seating and seal

Who is this for: The GM Genuine Parts GT347 (20962524) Fuel Tank Filler Cap is intended for owners and technicians who need an exact-fit, original-equipment replacement for compatible GM vehicles. It’s a practical choice for drivers focused on maintaining factory-spec sealing, preventing fuel loss and contamination, and ensuring the vehicle’s evaporative system functions as designed. Ideal for routine service, part replacements after loss or damage, or when diagnosing fuel-system or evaporative emission issues where seal integrity is critical.