A spread axle trailer features axles positioned more than 10 feet apart, creating a distinct configuration that revolutionized the trucking industry in the late 1980s. These specialized trailers quickly gained popularity among professional drivers for their superior weight distribution capabilities.
The most significant difference in a spread axle trailer is the axle rating. If the axles are 10 feet or more apart, they are considered two separate single axles. This allows for 20,000 lbs weight capacity per single axle, smoother weight distribution during load, and a smoother ride than using a traditional tandem setup.
Understanding the spread axle design is important for maximizing hauling efficiency. Greater distance between axles means better weight distribution across the length of the trailer, making it easier to conform to road weight regulations. This design is even more valuable in refrigerated applications where exact weight distribution is important to maintain the stability of the load and to stay legal on the road.
Since their inception, the spread axle trailer has been the trailer of choice for the savvy driver desiring to efficiently load out his trailer and enjoy overall improved handling characteristics along long-haul routes.
Benefits of Spread Axle Trailers
Spread axle trailers have many benefits that make them appeal to a majority of professional drivers. Better weight dispersion includes 20,000 lbs single axle capacity, a higher overall weight-carrying capacity, and is best for carrying heavy loads.
The process of loading becomes quite simple, with heavier cargo at the rear of the trailer and lighter items at the front. This eliminates continuous axle sliding adjustment and enables fast scaling without needing to weigh repeatedly.
Ride quality features provide an increased smoothness on highways, better stability during long hauling, no more trailer bouncing and vibration, and more care for the cargo during transit.
Advanced capabilities include electric dump valve for weight adjustment, air equalization systems between axles, available lift axle configurations for empty runs, and sliding axle options for versatility.
These features provide an effective hauling experience, very helpful during refrigerated trailer operations and moving heavy loads. This is because the spread axle configuration allows drivers to focus less on constantly adjusting the load, but rather deliver the goods efficiently. That is why it is so valued in professional trucking operations.
Common Disadvantages and Considerations
Spread axle trailers are not without operational difficulties for the driver to learn about! The extended distance between axles creates two main areas of concern.
Space management challenges include low maneuverability in tight spaces, inability to make very sharp turns, inability to access certain loading docks, and wider turning radius required.
Tire wear issues include tires easily rolling under the rims while making sharp turns, possible premature wear on tires while cornering, and tires can even be completely destroyed if not handled correctly.
Examples of such risks, from real-life situations, were when a driver attempted a tight corner with a custom-built spread axle trailer and had twisted crossers, broken airlines, and damaged cargo. It goes to show the importance of proper handling techniques and equipment quality.
In order to minimize these challenges, practice route planning to avoid corners with tight turns, wider turns to protect tire integrity, appropriate speed during cornering maneuvers, and consider electric dump valve technology for tight corners. These factors become all the more important in city centers or where there is very little room for maneuverability. Drivers who switch to a spread axle from a conventional trailer will require special training to modify driving behavior.
Advances in Spread Axle Technology
Spread axle trailers have also innovatively changed with added features to their performance and maneuverability. The electric dump valve technology, directly controlled from the cab, was one game-changing addition. It gave drivers the ability to selectively dump air from either the front or back axle in turn to shift weight for better traction.
Another major development is the air equalization valves. These complex systems work to automatically equalize air pressure between axles, no matter the spacing of the axles. This automatic adjustment ensures optimal weight distribution and improved handling characteristics across various road conditions.
For added versatility, many spread axle trailers are now fitted with lift axles. This modification proves invaluable when:
- Running empty loads
- Operating with lighter cargo
- Reducing unnecessary tire wear
- Improving fuel efficiency
Some owners have modified their rig to accommodate creative solutions, such as rerouting exhaust airlines through the floor of the trailer, with installed sliding axle mechanisms for set-backs of adjustable distances. Dual-control systems give various controls for both trailer and drive axles, which are the technological features that make spread axle-pulling trailers versatile for any situation.
One good example would be a 53-foot reefer with a 12-foot spread configuration that caters to just about any load and view for optimal weight conformance.
Recommendations for Optimal Spread Axle Operation
Here’s what experienced operators suggest to optimize spread axle operation:
- Load distribution – ask shippers to send heavier cargo to the rear of the trailer, placing one or two items up front for balance
- Scale management – unlike tight tandems, spread axles don’t need to be in-and-out of the Cat-and-mouse games at the scales
- Cornering – take it slow on tight cornering to maintain tire life and avoid rim damage
- Space Evaluation – Allow for careful planning of routes, considering the wider turning radius of spread axle configurations
Proper Maintenance for Spread Axle Trailers
Regular maintenance is important to extend the life of your spread axle trailer and ensure safe operation. Based on the unique design and weight distribution characteristics, here are the key areas to focus on in terms of maintenance.
Critical Maintenance Points
Regular inspection of air equalization valves, monitoring tire wear patterns (especially during cornering), checking cross members for structural integrity, and testing dump valve systems and air pressure controls are essential maintenance tasks.
Special Attention Areas
Floor cross members are subjected to twisting forces and should be given more scrutiny. Frequent airlines and pressure systems checks are necessary. Axle alignment must be checked or the tires will wear in uneven patterns.
A well-maintained spread axle trailer prolongs its life and optimizes its performance. Professional diesel mechanics can identify the telltale warning signs of structural stress and manage the unique air systems that keep these trailers moving.
Choosing the Right Service for Your Needs
Spread axle trailers are a big step up in trucking technology because they distribute weight much more evenly and make scaling simpler. However, like all things with a specialized design, they need specialized care. At Mac’s Diesel and Trailer Repair, we are aware of the specific problems that come up with spread axle trailers. Our diesel mechanics are knowledgeable in general spread axle maintenance, professional axle alignment services, air equalization system repairs, and troubleshooting dump valve technology.
Your semi’s performance and safety are our number one concerns. We take our talents to you with our mobile diesel repair services in Lexington, Kentucky, and the surrounding areas. Time to maximize your spread axle trailer? Have our expert team at Mac’s Diesel and Trailer Repair help keep your equipment operating at top performance.
Contact Mac’s Diesel and Trailer Repair
Give us a call today at (859) 433-4062 to schedule our professional mobile repair, DOT inspection, and emergency roadside assistance services. We serve the Lexington, Kentucky & surrounding regions.
Don’t wait any longer to schedule your appointment and discover the difference professional diesel repair service can make.