A side-by-side comparison of the top trailer side skirts

Trailer side skirts are a relatively simple accessory that can help improve fuel economy by anywhere from 4-7%, depending on which manufacturer you’re talking to. The independent North American Council for Freight Efficiency (NACFE) says a solid 2-3% fuel economy gain is a solid baseline expectation. For long-haul and line-haul fleets, the fuel savings can add up quickly—making it easy to justify the modest investment required to add a couple of side skirts to a trailer.

Today’s trailer side skirts are also engineered to bend, flex, and take a pretty good beating out in the field, making them a long-lasting product with minimal maintenance needs, barring any unforeseen circumstances.

Here’s a look at some of the top trailer side skirt options out there today.

Energy Guard Trailer Skirts are supported by brackets made of four thin stainless steel sheets. Initially very stiff, they can toggle and easily bend. When impacting an object, the skirt material flexes easily on the bracket. When the skirt bends, the springs slide through, preventing the bracket from putting tension on the skirt panel and protecting it from damage. Energy Guard also offers top fairings, wheel covers, and mud flaps.

FleetAero TrailerBlade Side Skirts are made up of steel panels with an LDPE (low-density polyethylene) core for flexion. The lower part of the skirt is made of TPV (thermoplastic vulcanite) rubber. The mounting strut is made of high-strength steel, engineered to pivot and articulate, and includes a triple-coated galvanization. Optional features include doors for access to spare tires, battery compartments, storage boxes, and tire chains. FleetAero offers other aerodynamic solutions including mud flaps, wheel covers, and the Rocketail that’s designed to reduce rear-end trailer drag.

Fruehauf offers Transtex side skirts (see below) as standard on its trailers, but will also install other aerodynamic options. The company considers factors like skirt weight, alignment with the bottom rail, and access doors also for skirt installs, and its product specialists will work with fleets to identify the best overall solution for a fleet’s needs.

Transtex Edge Skirts are made from glass-reinforced thermoplastic composite. They are supported by the company’s T-Flex Blue Bracket, which is engineered to bend without breaking under stress. In addition to side skirts, Transtex’s Edge Elite Aero System+ includes the company’s Edge Topkit+ and Edge Flaps.

Transtex has also released the patent-pending EDGE CABFLEX, an aerodynamic fairing designed to replace OEM cab extenders. Weighing 70 lbs., the fairing is light, durable, and hinge-free. 

Utility’s Side Skirt USS-120A-4 features one-piece construction, which reduces weight while increasing strength, and UV-protected Fiberglass Reinforced Plastic (FRP) material. The skirt has increased ground clearance and a securely bolted forward edge, using a “2 spring mount bracket” at the support leg assembly to reduce potential impact damage. It’s galvanized steel braces allow the skirt to flex inward and outward and can be bent back into shape if damaged. The USS-120A-4 is a standard feature on Utility’s 4000DX- Composite dry vans and 3000R refrigerated trailers.

Wabash’s DuraPlate AeroSkirt is constructed with DuraPlate composite panels and is installed with a spring bracket system that allows the skirt to flex inward and outward to resist damage. It also features two external steel skins thermally bonded to a high-density polyethylene core, a flexible thermoplastic lower section, and galvanized bracket hardware for corrosion resistance.

ZF’s OptiFlow TrailerSkirt consists of tough fiber-reinforced plastic panels and features a one-bolt mono-clamp system and flexible thermoplastic struts that hold up in both hot and cold conditions. Its heavy-duty brackets are made of a durable polymer. The OptiFlow TrailerSkirt is available in multiple lengths and standard black or white finishes. A newer addition is the compact 115” model, which provides flexibility for a wider range of trailer configurations. ZF also offers its OptiFlow Flap with a curved honeycomb design to reduce drag.