Frequently Asked Questions About Peterbilt 362 Fuel Tank Caps

Will these fuel tank caps fit my specific year Peterbilt 362?

Our Peterbilt 362 fuel tank caps are designed to fit models from 1980 through 1986. These caps feature the standard 4-inch diameter opening that was used throughout the 362 production run. However, if your truck has been modified with aftermarket tanks or has non-standard fuel necks, we recommend measuring your current cap diameter before ordering. The threading should match the original Peterbilt specifications of 8 threads per inch.

What's the difference between locking and non-locking fuel caps?

Locking fuel caps provide security against fuel theft and tampering, featuring a key mechanism that prevents unauthorized removal. Non-locking caps use a simple twist-on design for quick access. Both types seal equally well to prevent fuel vapor escape and meet DOT requirements. Locking caps typically come with two keys and add about 1/2 inch to the overall height compared to standard caps. Consider your parking situations and security needs when choosing between the two.

Are these caps vented or non-vented, and which do I need?

Most Peterbilt 362 models require vented fuel caps to allow air to enter the tank as fuel is consumed, preventing vacuum lock. Vented caps have a small pressure relief valve built into the design. Non-vented caps create an airtight seal and are typically only used on trucks with separate tank venting systems. Check your existing cap or consult your owner's manual - using the wrong type can cause fuel delivery problems or tank damage.

What materials and finishes are available?

We offer fuel caps in chrome-plated steel, polished aluminum, and powder-coated steel finishes. Chrome provides the classic shine but requires regular polishing to maintain appearance. Aluminum caps are lighter and naturally corrosion-resistant but may show scratches more easily. Powder-coated options come in black or custom colors and offer excellent durability for work trucks. All options include fuel-resistant rubber gaskets that should be replaced every 2-3 years for optimal sealing.

How do I know when to replace my fuel cap?

Replace your fuel cap if you notice fuel odors around the tank area, see visible cracks in the gasket, experience difficulty threading the cap, or if the locking mechanism fails. A worn cap can trigger check engine lights due to evaporative emission leaks. During inspection, check that the gasket is pliable and creates a complete seal, the threads engage smoothly without binding, and any pressure relief valves move freely. Most caps last 5-7 years with regular use before needing replacement.