How to Keep a Trailer Axle From Rusting in Salt Water

Clean the axle with a pressure washer to remove dirt and mud. Rent a pressure washer from most any tool rental store. Attach a green or yellow wand tip to the spray wand to clean the axle, and spray in slow strokes from left to right.

Wear rubber gloves and eye goggles before applying any chemical or grease solutions to the project. Spray metal cleaner onto the axle, paying special attention to rusted or corroded areas. Scrub the rust or corrosion from the metal using a brass wire brush. Clean all grease and grime, as well. Failure to fully clean the axle will impede new saltwater protection.

Dry off the axle with a cloth rag. Spray compressed air onto the axle to remove smaller beads of water or cleaner that may remain. Allow the axle to sit in direct sunlight for an additional 30 minutes before applying protective coating.

Apply white grease(synthetic grease) to the axle. Scoop the grease from the container with your glove-covered fingers, and wipe it directly onto the axle metal, distributing the grease evenly in 1/4-inch coats. Allow the grease to sit for 30 minutes, and reapply a second coat. The thick coat of grease will ensure full penetration of axle crevices and pits.

Remove remaining grease with a cotton rag, leaving a thin coat of no more than 1/8-inch. This thin coat of grease will provide six to eight months of axle protection, preventing saltwater corrosion and rust.