Getting over excited and over-springing the vehicle leads to a multitude of issues. The side-effects of too high a spring rate can include everything from poor ride and handling, too decreased off-road capability and premature shock wear or failure.
Naturally, when we load up the 4×4 with the vast amount of quality accessories on the market, the scales start tipping towards the point that the factory suspension just cannot cope with both the load and the punishing terrain that intrepid adventurers come across. That’s where a specialized suspension becomes necessary.
Tough Dog suspension normally offer a minimum of two or three spring rates for every vehicle to cope with different levels of constant load. The key is to match the leaf spring with the load that you constantly carry, not what you’re going to be carrying.
The original suspension in a standard vehicle is designed for a constant empty load for the occasional load at the back of the vehicle. Then there are service vehicles, which are generally fully loaded and on the move constant.
For this reason it is impossible to create spring which fits all vehicles and their intended uses.
In simple terms, a constant load spring is one that will hold a constant load at a specified height. So when we say ‘constant 300kg’ we’re saying the vehicle will be 40mm above standard height, when 300kg is in the rear of the vehicle.
When a Constant load spring is fitted without the load, effectively you’re lifting the vehicle too high. The result of that is that the shock’s resting position is nearly fully extended position, which means little to no down travel and the shock constantly running out of travel on and off-road which can lead to bush wear and shock failure.