When the all-aluminum horse trailer came on the market in the 1970s, pioneered by Featherlite Trailers, it had a huge advantage over steel as a manufacturing material. Not only did aluminum resist rust and corrosion, it was also lighter and therefore easier to pull. Trailer owners reporting better gas mileage when hauling an aluminum trailer only added to its popularity.
All-aluminum trailers tend to be more expensive than steel trailers, however. And steel trailer manufacturers claim aluminum trailers just can't withstand the stress of trailering as well as a steel trailer. This leaves buyers with a hard choice-do they pay more for an all-aluminum trailer with its supposed superiority, or buy a more familiar steel trailer and save money? Opinions vary wildly.
Featherlite Trailers feels aluminum trailers are the better choice. Here is some information that explains why.
Metallurgy for the masses
The big question to be answered is which metal is stronger. Steel trailer supporters like to point out that steel has a reputation of being one of the toughest common alloys, while aluminum is more commonly known for its use as foil or pop can material.
However, the aluminum used in all-aluminum trailers is an alloy, the same way that steel is an alloy of iron. This alloy has about the same yield strength as steel! It contains at least 95 percent aluminum, and the other five percent is composed of copper, titanium, chromium and zinc. Other metals are also added in trace amounts to further refine the alloy's properties.
Both kinds of trailers require upkeep, but the biggest issue with aluminum trailers is simply lubricating the hinges and cam latches. You'll also want to make sure to wash out the interior, since horse urine, for example, is corrosive. For cosmetic purposes, an aluminum trailer should be given an acid bath every couple of years to clean and renew its exterior.
Steel trailers, on the other hand, must be examined often in order to prevent rust. Any scratches in the paint need to be touched up or the steel will start to oxidize. If the steel has been galvanized or galvannealed though, you won't have to inspect the trailer as frequently, but you'll want to make sure that welded and riveted areas have been properly finished after every repair. The galvanic layer must be removed to weld, and rivets and screws compromise the galvanic coat.
This constant need to maintain the paint coat and the galvanic coat make steel trailer repairs more expensive, too. Steel trailer repairs are usually more expensive than similar repairs to an aluminum trailer because trailer dealers have to repaint it to prevent rust, while galvanized and galvannealed steel have to be stripped of their zinc layer before they can be welded. Then the zinc layer must be reapplied after repairs, and finally the repaired area gets a new coat of paint.
On the road again
So an aluminum trailer requires less maintenance, resists rust and corrosion and has better overall durability. It sounds impressive, but how do steel and aluminum trailers compare on the road? Horse and livestock owners who have owned both steel and aluminum trailers consistently say that they get a smoother tow with an aluminum trailer. They also say they can get a smoother ride with a loaded aluminum trailer than they get hauling an empty steel trailer!
The lower weight of an aluminum trailer also translates into a higher payload capacity, meaning you can load more items into an aluminum carrier before reaching the maximum amount of weight your vehicle will tow. Finally, as previously mentioned, several trailer owners reported better gas mileage towing an aluminum trailer than they did with a steel one.
Warranties and resale
The fact that steel rusts presents a problem when reselling it. Steel trailers only a couple years old often have patches of rust, which is difficult to cover or clean. Older steel trailers can be badly rusted, unsightly and even a safety hazard, with rust compromising load-bearing components.
On the other hand, aluminum trailer owners can keep their trailers running like new for decades with just routine maintenance. In terms of visual appearance, owners can restore their trailer's exterior with an acid bath that renders the trailer lustrous and pristine in minutes. These are just two reasons aluminum trailers command a higher resale price than steel trailers do.
As many trailer buyers have discovered, all-aluminum trailers have better warranties. All-aluminum trailer companies almost always offer longer warranties than steel trailer companies, which makes buying all-aluminum trailers a lower risk investment than buying steel.
As you may have noticed, all-aluminum trailers have several advantages over steel trailers. However, some articles on the Internet have talked about the problems with owning an aluminum trailer. These articles have only one flaw-their facts are often manipulated. Below are some of the popular myths about all-aluminum trailers, along with the real facts.
All-Aluminum trailers are as heavy as steel trailers. Aluminum is only 1/3 as strong as steel, so three times more aluminum must be used to get the equal strength of a steel frame
This would be a better argument if aluminum horse trailers or stock trailers were built from pure aluminum. However, the aluminum alloy used to construct these trailers is substantially stronger than pure aluminum. More aluminum is used, but the end result is still a trailer that weighs on average 10-15 percent less than a trailer made of steel. That translates to hundreds of pounds that can be added to cargo weight-or not pulled at all.
Trailer manufacturers aren't the only ones who have figured this out. Automobile and airplane manufacturers have been replacing steel with aluminum, and the majority of the NASA Space Shuttles' structures are constructed from aluminum alloys.
Steel is easier to repair than aluminum
Not anymore. Before aluminum became popular, more welders were familiar with welding steel and welding aluminum was another trick to learn. However, aluminum welding techniques are commonly known, and just about every welder knows how to work with aluminum. Consequently, the price has gone down as well, so the cost of getting an aluminum trailer welded is comparable to the cost of welding a steel trailer.
Aluminum stresses and tears more easily than a steel trailer
If aluminum is such an inferior building material, why is their resale value consistently higher than steel? Why do you rarely find a steel trailer warranty that's longer than the warranty on an aluminum trailer? For that matter, why do people who own aluminum horse trailers or stock trailers keep them longer on average than people who own steel trailers?
Now, if you want to be technical, steel is stronger than aluminum in some respects. It has a higher modulus of elasticity, for instance, which means more force must be applied to steel before it starts to bend. However, aluminum flexes three times as much as steel, which means that aluminum is more likely to spring back to its original shape after being stressed. Steel though, will probably stay bent. Steel also fatigues at lower levels of stress than aluminum, and steel's rigidity makes it more vulnerable to cracking because of its brittleness.
You might also be interested to know that aluminum's lower modulus of elasticity works in its favor as a construction material for trailers. A lower elastic modulus means that an all-aluminum trailer lessens impact shock loads while on the road, giving your animals a smoother ride and creating a smoother tow for your vehicle.
So-called "all-aluminum" trailers have steel parts, so steel must be superior
Not even close. Yes, "all-aluminum" trailer companies will use steel in certain areas, such as the trailer's axles. However, it is not because steel is better than aluminum. Rather, steel is better than aluminum in that instance. And that's one of the main differences between most steel trailers and all-aluminum trailers. All-aluminum trailers are not above using other materials to create the best possible product. On the other hand, most steel trailer manufacturers seem to insist that steel is the best material for every aspect of the trailer, regardless of whether or not another material might actually do a better job.
Of course, it's possible to take this concept too far. Some trailer companies have tried to get the best of both worlds by creating a steel frame and wrapping an aluminum skin around it. They advertise these trailers as being "aluminum" even though half-and-half might be a more accurate description. In theory, the steel frame makes the trailer stronger, and the aluminum skin lightens the trailer and resists rust. In practice, many of these half-and-half trailers can get worse mileage than a lighter all-aluminum trailer and the steel infrastructure is still prone to rusting, which can destroy the trailer's integrity. Worse yet, steel and aluminum chemically react to one another, so manufacturers must keep the two metals separate using Mylar padding or some other coating that separates the metals. This works fine in limited instances, but when this is applied to an entire trailer it can create problems. An owner of a half-and-half has to guard against the padding breaking down at every point on the trailer where the steel may come in contact with the aluminum. And if the trailer ever needs to be repaired, the padding usually has to be stripped and replaced as well.
The right metal for the job
The bottom line is that aluminum is a superior manufacturing material for trailers. While a steel trailer can do the job, an aluminum trailer almost always does a better job. It can last longer, too. You may save money initially, but after watching your trailer eventually rust and getting a replacement while your friends are still using an all-aluminum trailer, you'll know why so many people consider an all-aluminum trailer a superior value.