Jacking a 4×4 vehicle
CAUTION – Never get under any vehicle that is only supported by a jack.
4×4 Hi-lift Jack
By far, the best jack for 4X4’s is the Hi-lift type. It can lift virtually any vehicle and, with the aid of chains, it can be used as a winch.
The standard jack supplied with most 4X4’s can only raise the vehicle sufficiently to change a tire on paved roads or hard packed surfaces when the vehicle is not bogged. They usually rely on placing the jack under the vehicle in special spot on the frame or monocoque. If you try using this type when you are bogged to the chassis in sand or mud you’ll understand why it’s quite inadequate. The Hi-lift type jack can be used on any suitable part of the vehicle and can lift a larger amount of weight much higher than the standard jacks.
Some vehicles do not have suitable points to use a high lift jack due to the curved nature of their bodies and their bumpers. There are several types of jack adapters available to overcome this limitation. Hi-Lift makes an adapter that attaches to the lip of the underside if the curved bumpers. An adapter is also made that works well with the ARB Bull Bars.
It is best to have a jack plate around 300mm x 300mm when jacking on sand or mud to stop the jack burying itself. 7 ply plywood or 3.5mm steel is ideal, or if you carry a braai plate, this may be suitable. To test your jack plate, place 2 bricks 200mm apart with the jack plate on top; Slowly jack the vehicle while observing the plate. If it survives this without distortion it should be suitable.
A Hi-lift can be used as a jack with the aid of suitable chains. The top of the jack is attached with a chain to a suitable anchor point while another length of chain is attached to the bogged vehicle. On the bottom end of the jack is attached a length of chain with a clevis hook, while on the moving leg of the jack is attached a chain with a clevis claw.
This allows the jack to pull the vehicle approximately one metre and then attach the clevis hook while lowering the jack. The clevis hook stops the vehicle from moving back as the jack leg is lowered, ready to move the vehicle one metre again. This process is repeated until the vehicle is free.
4×4 Exhaust Bag Jack
The exhaust powered bag type of jack is very simple and easy to use, provided it can be placed under part of the vehicle. It is quite effective, especially in sand where, if necessary, a small area can be dug away to accommodate it. It requires the vehicles exhaust system to be in good condition as even a small hole will prevent the bag from inflating. It can also cause rusted or weak areas in exhaust systems to blow out.
Be sure when placing the bag under the vehicle that sharp objects are clear from the bag to avoid puncture. Once in position, connect the pipe to the vehicle exhaust and start the engine (in neutral). When the wheel is clear stop the engine and simply fill in the hole or rut with whatever is available or dig away any sand that has built up.
