A trolley jack, sometimes referred to as a floor jack or service jack, is a piece of automotive equipment that is used to lift a vehicle off the ground. Trolley jacks can be used as a temporary support while vehicle maintenance is being carried out.
There are two main varieties of trolley jacks – mechanical or hydraulic. The majority are hydraulic as these allow you to lift more weight with a smaller device. Mechanical jacks rely upon the physical strength of the user to help lift the vehicle. Trolley jacks are normally fitted with casters or wheels that swivel, making them versatile and suitable for use with a number of different types of vehicle. Trolley jacks are suited to low profile vehicles.
Trolley jacks are typically constructed from steel or aluminium and have been designed for use on flat, hard surfaces. If you are looking for a more portable vehicle jack, a bottle jack may be more suitable.
To use a trolley jack, you need to pump the handle that is connected to the jack. For hydraulic floor jacks, pumping the handle pushes pressurised oil into the main cylinder and causes the main piston to raise. This will continue as you pump the handle. The piston will then connect with the arm and saddle of the floor jack, which in turn will lift the vehicle off the ground.
The choice of trolley jack depends on the weight that you want to lift. This is measured in tonnes and options range from 0.5 tonnes (500 kg) all the way through to 10 tonnes (10,000 kg).
Trolley jacks are relatively low maintenance, but you should bear in mind that the oil within the main cylinder of the jack will need replacing at times. Keeping the jack lubricated will enhance its lifespan and maintain all of its functionality. After use, you should always release the oil pressure before storing your floor jack.
Trolley jacks are a piece of lifting equipment and should not be used to load bear. Once it has been lifted, the vehicle should be placed on supports (such as axle stands) whilst the maintenance or repair is being carried out.
You must not overload a trolley jack by trying to lift more than its maximum weight capacity. This can cause the jack to fail and could cause injury and damage to the vehicle. Some models have a safety system inside the hydraulic system that stops the jack from being overloaded.