Even though aftermarket springs – whether coil or leaf – may be classified as ‘Heavy Duty’, they are not designed to allow you to load your 4WD above the GVM (gross vehicle mass) specified by the vehicle’s manufacturer.
Popular additions to touring vehicles include, bull bar, winch, long-range fuel tank, water tank, drawer system, fridge, extra spare wheel, roof rack and recovery gear. Add to this some passengers, camping equipment, food and drink, plus fuel, and there is a good chance the GVM of the vehicle has been exceeded.
It pays to check that the weight of your vehicle is below the legal limit before starting on your trip. Failure to observe the manufacturer’s GVM is irresponsible, and can lead to serious ramifications if you have an accident.
Some suspension businesses advertise ‘GVM Upgrades’. However, while the replacement suspension may be ‘beefier’, the vehicle manufacturer may still void any warranty; as the GVM rating also takes into account the equally-important specification of the driveline and braking system.
[Extract from 2013 4Way Suspension Catalogue, Marque TT&W, July 2013]