Summary
Hydraulic and pneumatic jacks are the most common. They can be mounted
on slides or on a wheeled trolley. The size of jack you use will be
determined by the weight of the vehicle you want to lift. The objective
of this procedure is to show you how to lift and secure a vehicle with a
floor jack and jack stands.
Part 1. Preparation and safety
Objective
- Lift and secure a vehicle with a floor jack and jack stands.
Personal safety
Whenever you perform a task in the workshop you must use personal
protective clothing and equipment that is appropriate for the task and
which conforms to your local safety regulations and policies. Among
other items, this may include:
- Work clothing - such as coveralls and steel-capped footwear
- Eye protection - such as safety glasses and face masks
- Ear protection - such as earmuffs and earplugs
- Hand protection - such as rubber gloves and barrier cream
- Respiratory equipment - such as face masks and valved respirators
If you are not certain what is appropriate or required, ask your supervisor.
Safety check
- Make sure the jack and stands you are using are suitable for the job.
- Never lift a vehicle that is heavier than the jack's rated capacity.
- Always use matched pairs of jack stands.
- Never support a vehicle on anything other than jack stands.
- Do not use wood or steel blocks to support the vehicle. They may slide or split under the weight of the vehicle.
- Do not use bricks to support the vehicle. They will shatter under the weight of the vehicle.
- Make sure that you understand and observe all legislative and
personal safety procedures when carrying out the following tasks. If
you are unsure of what these are, ask your supervisor.
Points to note
- There are three types of workshop jacks: hydraulic, pneumatic and mechanical.

- Hydraulic and pneumatic jacks are the most common. They can be mounted on slides or on a wheeled trolley.
- The size of jack you use will be determined by the weight of
the vehicle you want to lift. Most workshops will have a jack that has a
lifting capacity of about 2 ½ tons/tonnes. If the vehicle is heavier
than that, or if the vehicle is loaded, you will need to use a jack with
a larger lifting capacity.
- Always check the vehicle service manual or owner's manual to
determine the best position to support a vehicle. Some vehicles require
special attachments to be fitted before they can be lifted.
- Do not jack or support a vehicle under any independent
suspension components. They are not strong enough to support the weight
of the vehicle.
- Make sure the vehicle is positioned on a firm level surface.
- Make sure the jack stands are in good condition before you
use them to support the vehicle. If they are cracked or bent, they will
not support the vehicle safely.
Part 2: Step-by-step instruction
- Position the vehicle
Position the vehicle on a flat, solid surface. Put the vehicle
into first gear or park and set the emergency brake. Then place blocks
in front of and behind the wheels that aren’t going to be raised off the
ground. - Inspect the floor jack
Before you try to use the jack, check for leaks in the hydraulic
system. Check the pad, or saddle, and the wheels of the jack. They
should rotate freely and show no signs of damage. Check the
manufacturers’ label on the jack. The specifications will tell you the
maximum load weight it will bear, so it must suit the vehicle you want
to raise. - Check the vehicle handbook
Refer to the owner’s manual to find out where you can safely
place the jack. This is usually a major point on the chassis, a cross
member or axle unit. - Select the jack safety stands
Before operating the jack, select two safety stands of the same
type, suitable for the weight of the vehicle. Check the stands for any
cracks, and if necessary lubricate the threaded adjusting post with a
few drops of engine oil. Place one stand on each side of the vehicle at
the same point. Adjust them so that they are both the same height, and
high enough to slip under the vehicle once you’ve raised it. - Position the jack
Roll the jack under the vehicle, and make sure the pad, or
saddle, is positioned correctly under the frame or cross member. Turn
the valve on the top of the jack handle clockwise, and begin pumping the
handle up and down until the jack pad touches and begins to lift the
vehicle. - Check position of jack
Once the wheels lift off the floor, stop and check the placement
of the jack pad under the vehicle to make sure there’s no danger of
slipping. Double check the position of the wheel blocks to make sure
they haven’t moved. If the vehicle is stable, continue lifting it until
it’s at the height where you can safely work under it. - Position the safety stands
Slide the two jack safety stands underneath the vehicle. Make
sure they’re positioned at a point that can support the weight. Both
stands should be adjusted to the same height and placed as far apart as
practical. - Lower the vehicle onto the stands
Turn the valve on the jack handle counter-clockwise and gently
lower the vehicle onto the stands. When the vehicle has settled onto the
stands, lower the jack completely and remove it from under the vehicle.
Repeat this process to lift the other end of the vehicle. Be aware that
the vehicle is now supported on jack stands and will not be as stable
as it would if the wheels were on the ground. When you’ve finished
working under the vehicle, make sure you’ve removed all tools and
equipment before you attempt to lower it. - Raise the vehicle off the stands
Use the jack to raise the vehicle off the safety stands. Slide out the safety stands from under the vehicle. - Lower the vehicle
Turn the valve on the jack handle counter-clockwise very gently
to lower the vehicle to the ground. Do not allow the vehicle to drop
quickly or you may cause serious damage. Return the floor jack, the
safety stands and the wheel wedges to their storage area before you
continue working on the vehicle.
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