MRAP SUSPENSION UPGRADES
Published: 12/18/2010 by Paul Douglas MRAP Expert
As militaries try to modernize with limited budgets, this is one way of improving your MRAP without purchasing a new fleet of MRAP.
INDEPENDENT OR SOLID BEAM AXLE?
As the MRAP type armored vehicles have evolved over the past few years, one of the biggest changes by demand from the USG is the configuration of the suspension system.
Naturally a truck as heavy as the average MRAP type configuration suggested a solid beam type design. Solid beam axles are very common on heavy trucks in both civilian and military use.
The variation of suspension systems on the first MRAP trucks produced is considerable. Some of these designs are in all honesty poorly conceived. One design did not even have shock absorbers mounted on the rear axle. This made off road performance impossible. I still canï¿½t understand how that concept was produced.
The USG began demanding a better suspension system for managing the terrain in Afghanistan. Iraq never really forced the USG to consider independent suspension systems. But serious terrain conditions in Afghanistan initiated a re-think of designs.
Independent suspension does provide a smoother ride and will give better off road performance if it is properly designed for the vehicle it is being applied to.
There are 2 basic designs being applied to MRAP now. One from Oshkosh and one from Alex Tech. The main differences between the two are size and drum brakes (Oshkosh) and disc brakes on Axle Tech.
One disadvantage to drum brakes is the size of wheel required. If the system is installed as a replacement suspension or a modification to an existing truck design, the turning radius maybe reduced considerably.
The concept of independent suspension allows each wheel to move independent of the other wheel on a given axle. This gives a much better footprint on the terrain. If all wheels are grounded in off road operation, they will provide traction. Naturally if the terrain exceeds the travel of the wheel, it will loose its footprint and not give traction.
In fairness to solid beam designs, this can be as effective with solid beam designs but the design must allow flex and suspension travel to maintain a footprint.
If an existing design to an MRAP type truck is modified, its important to consider the basic engineering change that will be affecting the basic design characteristics of the truck. As an example: total vehicle height, turning radius, payload capacity, gear ratio compatibility with transfer case, ground clearance just to name a few considerations. If the program is well thought out from an engineering perspective, the truck will perform better than originally designed.
In order to have quality off road performance, it is imperative to ensure the ground clearance is maintained or improved to ensure the truck is not susceptible to hanging up on terrain.
These are just s few points to consider about MRAP suspension systems. As a given rule, independent suspension is proving to provide better performance as new technology creates a better handling MRAP.
Written by Paul Douglas
Nu Pro Consulting LTD
Mine Resistant Ambush Protected