When a tank is partially empty for long stretches, the empty space allows moisture to accumulate inside—moisture combines with oxygen and any residue in the tank to trigger rust.

By maintaining a consistent fuel level, you reduce the amount of air (and thus moisture) that comes into contact with the tank's inner surface.

Many reputable fuel brands add corrosion inhibitors to their gasoline to slow down rust and corrosion inside fuel systems. Avoid using low-grade or unbranded gasoline, as it may lack these protective additives.

Over time, consistent use of quality fuel creates a thin, protective layer on the tank's interior, shielding it from the effects of moisture and fuel byproducts that can cause rust.

The outer surface of the fuel tank is exposed to road salts, dirt, water, and debris—all of which can scratch the tank's coating and lead to rust.

Regularly clean the area around the tank (such as the undercarriage of the vehicle) to remove built-up salt and grime.

Garages or storage spaces with high humidity levels increase the risk of moisture settling on the tank's exterior and seeping into any small cracks or openings.

If you need to store the vehicle for a long time, park it in a dry, well-ventilated space.

Check both the interior (if accessible) and exterior for early signs of rust, such as discolored spots, flaking paint, or small pits.

If you notice any signs of rust, address them immediately—small rust spots can be cleaned and treated with a rust converter to stop further spread.