How to Clean Aluminum Trailers

by TJ Hinton

Do not use strong acid-based cleaners to clean your aluminum trailer. Powerful acids can etch the surface and not only ruin the polished finish, but can make it difficult or impossible to regain any sort of high-luster finish. Only use products specifically formulated for cleaning aluminum to prevent this damage and protect the newly cleaned aluminum.

Removing Oxidation

Unfinished aluminum is particularly vulnerable to the corrosive effects of salt in a marine environment and in areas where winter road treatment is commonly used. Use a purpose-designed product such as 3M Marine, CLR, Aluminox or the environmentally friendly Bio-Kleen by Aluma Kleen according to the product instructions. Rinse the trailer thoroughly with fresh water regardless of the service environment, use the cleaning product, then rinse the trailer again with fresh water to remove all vestiges of the cleaner when finished. Most acid-based cleaners will etch concrete, creating a clean spot that will not match the rest of your driveway, so you must flush any undiluted runoff with copious amounts of water to neutralize the pH and prevent this collateral damage.


Once the sheen of your trailer is lost to the corrosive effects of salt, and to a lesser degree normal weathering, you must use mechanical means to restore it. Usually this involves a lot of hard work and a selection of abrasive products such as wet-dry sandpaper and steel wool in a variety of coarseness ratings. Start with fine paper, such as 220 grit, and work using a pattern that puts a crosshatch pattern on the aluminum. Rinse the paper with water frequently to prevent clogging and remove any large particles that may produce scratches that are too deep to polish out in subsequent polishing passes. Repeat the pattern using progressively finer paper, then steel wool, until all of the scratches from the previous pass are completely gone. Work down through the grades of steel wool until you achieve the desired sheen. Once you are satisfied with the sheen, apply a coat of automotive-grade wax to protect your work, as the freshly polished aluminum will be very vulnerable to oxidation and will begin to oxidize almost immediately.

After Each Use

Rinse thoroughly using clean, fresh water and inspect the trailer for aquatic hitchhikers if you've just pulled your boat out of the water. Exercise caution around the light fixtures and bearings if you are using moderate- to high-pressure water, to prevent introducing water into these components and causing damage. Scrub the trailer with a soft nylon brush while rinsing to remove road grime or particulates that may scratch the finish when you wipe it dry. Wipe the trailer down using a microfiber cloth, and never use a dirty rag or materials that may contain man-made fibers that can leave a patina on the trailer. Trailers with drum brakes are usually equipped with a flushing attachment on the drums, and it is necessary to flush these with fresh water after immersion in salt water as part of your after-use cleaning procedure.

Before Storage

When you are storing your trailer for the off-season, you should clean and wax the trailer as you would after polishing and daily use. If you use the trailer to transport a boat, and the rear wheel bearings become submerged as a matter of course, then repack your wheel bearings to remove any water that may be lingering in the bearing cavity. Trailers that are equipped with Bearing-Buddies will not need to be repacked, but you should pump the reservoir full of grease and tow the trailer a few miles to allow the fresh grease and spring pressure to displace any water present in the system.

About the Author

TJ Hinton trained as an auto mechanic at Mississippi Gulf Coast Community College and then later graduated from MMI as a certified motorcycle mechanic . He's also worked for 20+ years in home construction, remodeling and repair. His articles appear on and

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