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WORDS : PHILIP LORD

The suspension design your 4WD has can make a difference to how well it tows , and how much it can tow . Of course , there are many other factors in the mix for good towing stability , such as how the suspension is tuned , and the dimensions of the vehicle itself , not to mention how well the caravan is designed and how its load is placed for stability .

But if a tow vehicle has the suspension design basics well covered , that ’ s a good start .

MAIN SUSPENSION TYPES

There are exceptions to the rule but , generally speaking , 4WD suspension comes in a leafspring or coil-spring live axle design , or coil-spring independent suspension .

There are two basic parts of a suspension system : the springs , and the components they attach to – either independent suspension arms or a live axle , which in turn attach to the wheels . Of course , dampers ( or shock absorbers ) are part of any suspension system , too .

LEAF SPRINGS

Leaf springs are a very simple suspension type that , in principle , has been used since the horse and cart days . They are , effectively , curved strips of steel that are sandwiched and secured together by shackles . One spring typically has eyelets at each end so that the leaf pack can be secured to the chassis .

The number of leaves used depends on the weight the springs need to carry ; most vehicles will have a leaf pack of three or four leaves each side .

Leaf springs are generally very good at carrying heavier loads . They can accommodate the additional loading in a 4WD , from kerb weight to GVM , without a drastic change in its ability to absorb bumps .

The iconic 80 Series Cruiser has coil all-round .