Many trucks that you see on the road are the tandem trucks like firetrucks or water, tanker, and dump trucks.
Moreover, they are usually used for commercial purposes as they are suitable for hauling heavy loads and large volumes of liquid materials like water and oil.
What is a Tandem Truck? A tandem truck is a vehicle with two rear axles and only one front axle with two wheels on each end. It is a dual-axle truck that can transport heavier loads as its loading capacity is 12,500 to 28,000 pounds. Moreover, it is 9 feet 10 inches to 11 feet 4 inches long, 8 feet 6 inches wide, and 20 to 25 feet long. Furthermore, it is easy to change the position of the axle to distribute the weight on a vehicle according to the loaded weight.
The tandem trucks cost around $100,000 to $150,000, depending on their size, age, and performance. You can get used trucks at lower prices, around $35,000 to $50,000.
It is better to get these trucks when you do not need a larger dumping vehicle to cut off the overall cost; otherwise, the single-axle trailer can be a good option.
What is the meaning of a tandem truck?
The tandem trucks are named so due to the rear axles as they are arranged in a tandem pattern means one after another.
It has three axles; one is on the front end, while the remaining two are on the back end, present at a close distance.
Each axle has two wheels in most cases to improve traction and increase the vehicle’s stability. It is also known as a dual-axle truck due to the two axles on the back end.
In addition, tri-axle trucks have three axles that are lighter in weight and are also used for dumping purposes.
It relies on the rear wheels as the transmission sends power to the rear ones, and the forward tires are free to steer the vehicle.
Moreover, it is also known as a double-trailer, or double-bottom, due to the presence of a long rig that consists of a tractor on the front side and two trailers that can be attached to other side of rig.
History of Tandem trucks
The first tandem trucks were designed in Chicago in 1926 by an automobile designer named Magnus Hendrickson. His sons George and Robert helped him in the designing process.
Moreover, they used a metal beam to connect the axles by a single pivot for even distribution of the weight of loaded material.
Accordingly, it also helped reduce adverse effects on its performance when driving on uneven terrains and allowed it to maintain stability.
Their designed suspension became popular in the past as it increased the vehicle’s loading capacity and made it suitable for commercial purposes.
Hendrickson Motor Co. had the offer to sign a contract with International Harvester Company for providing a right to use the tandem suspension.
They are known for loading heavy-weight items and ensuring a smooth ride on rough and uneven terrains.
In addition, they provide better traction due to multiple wheels that make them stable on the road.
Hendrickson manufactured these trucks and tandem suspensions till 2011, but several modifications have been introduced in their traditional design till now.
What is the load capacity of a tandem truck?
They are known for their high loading capacity, which makes them ideal vehicles for commercial use.
A dual axle can carry more weight than a tri-axle and have better hauling capabilities to carry heavier objects for a long distance.
Moreover, both front and rear axles are engaged in moving the vehicle forward, whether the road is smooth or uneven, as they have to maintain balance on rough surfaces.
The axles can be locked by sliding, but it is better to avoid the axle locking unless the truck stops at a point. The larger tandem trucks can carry almost 25,000 to 28,000 pounds weight.
However, the smaller ones can transport around 12,500 to 15,000 pounds weight due to better loading capacity.
In addition, it has spring packs that can help withstand the stress of load and transport heavier material.
The total weight of the tandem vehicle is around 50,000 to 52,000 pounds, much more than a regular truck that can transport heavy loads.
What is the size of a tandem truck?
Tandem trucks are almost 9 feet 10 inches to 11 feet 4 inches high, which means they have an average height compared to other commercial vehicles.
In addition, it is around 8 feet and 6 inches wider, excluding the size of mirrors that will increase its width up to 9 feet and 4 inches.
These vehicles are extended from 20 to 25 feet horizontally, which is not more than the average length of commercial trucks.
Furthermore, they are designed to be longer and wider to improve loading space availability, making them ideal vehicles for carrying multiple products.
The triple-axle truck is designed to be almost 22 to 25 feet long on average, but it cannot haul heavier objects.
Is it possible to slide the axle position on the Tandem truck?
You can change the axle position on a tandem truck to modulate its weight-carrying capacity. Accordingly, weight distribution can be easily adjusted by changing axle positions.
A sliding rail is present just above the rear axle assembly in a single place due to pins that keep tandems locked.
Accordingly, you have to locate the sliding release arm to lock it into its place and release the pin. It is present on the front side of the rear axle assembly.
Drive it in a back-and-forth motion to release the pin if it gets stuck and becomes difficult to get out of the sliding arm.
It is essential to change the axle positioning by engaging the brakes.
When you have reached the desired position, stop and release the arm from its locked position and check the alignment of the lock holes.
The pin has to align with one lock hole to lock the trailer into an ideal position. Then, you have to move it again to align the pins with the lock holes that are present on the rack.
Check all the pins that have to be in a locked position before hauling the load to ensure safety. This way, you can change the axle positions in a few minutes.