Three types of three-axle truck drives, which model is more popular

Currently, three-axle models are available on the market in three arrangements: 6×2 front dual steeringing axle, 6×4 rear dual drive axle, and 6×2R rear dual axle single drive.

From the point of view of vehicle cost and cargo carrying capacity alone, also as a three-axle model, the 6×2 front dual steeringing axle model has an advantage over the other two in terms of cost and overall vehicle capacity.

Under the same configuration, it is more than 500kg lighter than the reardual axle, which means that it can load 500kg more cargo under standard load condition.

The 6×2 front dual steering axle has single tires on both front axles, while most rear dual axles on rear dual axle models have a dual tire configuration. The front axles also weigh and cost less than the rear axles.          

For the same overall vehicle length, the 6×2 front dual steeringing axle has better steeringing performance than the rear dual axle model.

The front dual steering axle model has a smaller distributed wheelbase compared to the 6×4 and 6×2R, resulting in a more favorable overall stress on the frame.

As the front axle of the rear dual axle model is subjected to a larger load, the selected steeringing gear will also be larger. Used in larger wheelbase trucks, it will lead to the frame load capacity concentrated in the front axle and rear balance shaft position, which is very unfavorable for the frame load.

Meanwhile, the rear dual axle model has 2 more tires, which is larger than the front dual axle model in terms of load carrying capacity. Under the same load, a smaller tire size can be used.

The 6×4 rear dual drive axle is better than the 6×2 front dual steering axle model in terms of driving ability, braking ability and gradeability.

From the market point of view, most of the trucks use 6×2 front dual steeringing axles, while most of the dump trucks use 6×4 rear dual axles. The main reason is that the 6×2 front dual steeringing axle has better steeringing performance, and the working condition of the truck is better, and the overload working condition is less. The total mass and vehicle cost are better than the rear dual axle model, and can meet the requirements of the total mass limit.

The 6×2 front dual steeringing axle is suitable for models with smaller loads, better working conditions and lower requirements for overload capacity of the rear axle.

Most of the 6×4 rear dual axle models are dump trucks, which mainly rely on the advantages of its rear dual axle's carrying capacity and the number of tires to get high overload capacity.

Strong driving ability of rear dual axle and strong braking ability of dual rear axle can meet the requirements of dump truck with short wheelbase, high load bearing and poor road condition.

Especially when dump trucks are unloaded, the rear axle carries a larger load. The carrying capacity of rear dual axle can better meet the demand of axle load transfer than rear single axle.

Therefore, 6×4 rear dual axle models are mainly used in short wheelbase, high rear axle load bearing and poor working conditions.

The 6×2R Rear Dual Axle Single Drive has most of the advantages of the 6×4 Rear Dual Drive Axle, and is only slightly inferior to the Rear Dual Drive Axle in terms of driveability.

At no load and low load, it reduces fuel consumption and improves dynamics by reducing rolling resistance, and can reduce tire wear.

Hopefully, the above comparison has given you an idea of the three drive forms of tri-axle trucks. In terms of load, the rear dual axle is the most compliant with the regulatory requirements, and the dual drive and single drive can be chosen according to the demand.

The 6×2 front dual steeringing axle model, although not ideal for axle load distribution, compensates by choosing a rear axle with a larger load carrying capacity. It is most widely used in cargo vehicles due to its cost and overall mass advantages.