Aluminum Trailers vs Steel Trailers

At PROLine Products, we only build aluminum framed trailers. Not because aluminum is the perfect material in all circumstances but it is the better material in most circumstances, especially for trailers in the northeast. This comes down to a couple key factors.

Rust & Corrosion

Both metals, aluminum and steel, will undergo oxidation. The greatest difference lies in how this oxidation affects the strength of each metal. Steel oxidizes and forms iron oxide, or what is commonly referred to as rust. Aluminum oxidizes and forms aluminum oxide, something you may never have heard of but is very, very important.

When steel is exposed to oxygen and moisture it begins oxidizing immediately. This oxidation is a continuously detrimental process. The metal will rust, which exposes new steel, which will rust, and so on and so forth until your trailer is broken down on the side of the road. The presence of salt, which is a main component of winter road treatment, acts as a catalyst to the formation of rust. You can probably now see why geography has an affect on material choice.

Many trailer manufacturers located in the southern part of the United States strictly build steel framed trailers. These trailers in a warmer climate don’t have to worry about snow. No snow means no salt on their roadways to speed up the formation of rust, it also means they don’t have to worry about potholes in the roads, or snow falling on their roofs which is an entirely different point that we won’t continue here.

To slow the formation of rust, steel framed trailers are painted by their manufacturers to prevent the steel from being exposed to the elements. This paint needs to be free from scratches or chips to be effective. Therefore it’s imperative that a steel trailer’s finish is kept up with and may need to be repainted or touched up year after year.

Once rust starts on a steel framed trailer the strength of the metal will begin to deteriorate. If this continues the result is an eventual catastrophic failure of the component.

Aluminum oxidation actually enhances the stability of the aluminum. The oxidation layer will form and stay microscopically thin, preventing further oxidation. This protective layer will stay in place until it gets scratched off or cleaned with an acid wash, at which point it will regenerate. With no paint to maintain aluminum trailers require minimal maintenance compared to their steel counterparts.

Strength & Weight

Both metals are inherently strong and the better material choice depends on the application, plows and dump trucks are made of steel whereas airplanes and space ships are made from aluminum. Steel is a more rigid alloy, meaning that it’s more resistant to flexing. Steel also has a better fatigue strength so it does a better job of withstanding repeated impact loads.

Where aluminum shines is its strength to weight ratio, which beats out steel by a factor of roughly 3:1. This allows aluminum trailer manufacturers to reinforce their aluminum trailers to overcome the rigidity and fatigue restrictions mentioned above. Even after the additional reinforcement you will still end up with a lighter weight trailer that’s as strong or stronger, without the risk of corrosion.