Gates 31858 Fuel Tank Cap

Gates 31858 Locking Fuel Cap Overview

The Gates 31858 Regular Locking Fuel Cap is a direct-fit fuel tank cap for select Chevrolet and GMC applications. It is built to meet OEM specifications and emission requirements while helping seal the fuel system with a lockable design and pressure/vacuum relief function.

Gates Regular Locking Fuel Cap line focuses on OE-style fuel tank sealing for everyday service replacement. This product line is built for vehicles that need a regular fuel cap with locking security and controlled tank venting.

• Lockable regular fuel cap for fuel tank security
• Pressure/vacuum relief valve helps the tank breathe while limiting fuel vapor escape
• Quick-On cam type for proper cap engagement
• Thread diameter: 1.56 in.
• Shell diameter: 2.91 in.
• Depth: 2.22 in.
• Built to meet OEM specifications and Federal and State emission requirements

Detailed Fitment and Application

This Gates 31858 fuel tank cap is compatible with select Chevrolet Express, Silverado, Astro, Volt, and GMC Envoy and Savana models. It is a practical replacement for drivers searching for a locking fuel cap for 1997-2012 Chevrolet and GMC vehicles, including a Gates 31858 replacement for Chevrolet Express 1500 fuel cap service and GMC Savana fuel tank cap applications.

Fits 2011-2012 Chevrolet Volt, N/A. Fits 1998-2005 Chevrolet Express 1500, N/A. Fits 1998-2005 Chevrolet Express 2500, N/A. Fits 1998-2005 Chevrolet Express 3500, N/A. Fits 2005 Chevrolet Silverado 2500, N/A. Fits 2002-2004 GMC Envoy, N/A. Fits 2002-2004 GMC Envoy XL, N/A. Fits 2004 GMC Envoy XUV, N/A. Fits 1997-2003 Chevrolet Astro, N/A. Fits 1998-2003 GMC Savana 1500, N/A. Fits 1998-2003 GMC Savana 2500, N/A. Fits 1998-2003 GMC Savana 3500, N/A. Fits 2002 Chevrolet G30, N/A.

This part cross-references Four Seasons 35081 for the same application.

What This Fuel Cap Helps Address

• Loose or damaged fuel cap sealing
• Fuel vapor leakage from a worn cap seal
• Check engine light concerns related to fuel tank sealing
• Difficulty maintaining proper tank pressure or vacuum balance
• Need for a locking replacement fuel cap on select Chevrolet and GMC models

Installation Notes and Quality Assurance

Verify the cap style, thread diameter, and cam type before installation. Confirm vehicle fitment by year, make, and model, then install the cap until it seats fully and locks as required. For best results, inspect the filler neck and sealing surface for wear or debris before replacing the cap.

Gates manufactures this fuel cap to align with OEM specifications and emission-related requirements for the listed applications. Part number 31858 is a Gates replacement fuel tank cap for select Chevrolet and GMC vehicles.