Frequently Asked Questions About International 9300/9370 Fuel Tank Caps

Will these fuel tank caps fit my specific International 9300 or 9370 model year?

Most aftermarket fuel tank caps for International 9300 and 9370 models are designed to fit trucks manufactured from 1987 through 2007. However, International used different tank neck sizes during this period - typically either 2-inch or 2.25-inch diameter openings. Before ordering, measure your existing fuel tank opening or check your original cap for size markings. Some 9300 models from 2003-2007 may have different threading patterns, so double-check the product specifications against your truck's year and VIN if you're unsure.

What's the difference between vented and non-vented fuel caps, and which one do I need?

Vented fuel caps allow air to enter the tank as fuel is consumed, preventing vacuum buildup that can cause fuel flow problems or tank damage. Non-vented caps create a complete seal. Most International 9300/9370 trucks require vented caps for proper operation. If your truck stalls after running for a while, makes a hissing sound when you remove the cap, or the fuel tank appears to be sucking inward, you definitely need a vented cap. Check your owner's manual or look for "vented" markings on your original cap to be certain.

Are locking fuel caps worth the extra cost for my International truck?

Locking fuel caps typically add $15-30 to the cost but provide essential security against fuel theft and tampering. With diesel prices and theft rates increasing, most owner-operators consider them a worthwhile investment. Look for caps with sturdy brass tumblers rather than cheaper zinc locks, and ensure they come with at least two keys. Some fleet operators prefer keyed-alike systems where one key works for multiple caps, which is available from several manufacturers.

How do I know if my fuel cap is causing my check engine light or emissions problems?

A faulty fuel cap is one of the most common causes of evaporative emission (EVAP) system codes on International trucks. If your check engine light comes on with codes P0440, P0442, or P0455, first inspect your fuel cap's rubber gasket for cracks, wear, or deformation. Even a slightly damaged seal can trigger these codes. Try cleaning the tank neck and cap threads with a wire brush, then hand-tighten the cap until you hear 3-4 clicks. If the light persists after several drive cycles, the cap likely needs replacement.

What material and finish options hold up best against weather and road chemicals?

For maximum durability on International 9300/9370 trucks, choose fuel caps made from either heavy-duty aluminum with anodized finishing or stainless steel construction. Chrome-plated steel caps look attractive but can pit and rust within 1-2 years in areas using road salt. Powder-coated aluminum caps offer good corrosion resistance at a moderate price point. Avoid basic painted steel caps unless you're looking for a temporary solution. The gasket material is equally important - look for caps with Buna-N or Viton rubber gaskets rather than standard rubber for better fuel resistance and longevity.