- The basic function of a car jack is to lift a portion of a vehicle. Typically this is used to change a tire although other maintenance is sometimes performed with the use of a car jack. Car jacks normally lift one corner of the vehicle, but larger capacity jacks of a more specialized type can be used to lift the entire front or back of the vehicle under certain circumstances.
- The primary type of car jack issued by automotive manufacturers is the scissor-jack. This type of jack uses a central screw mechanism to raise and lower the jack. The screw mechanism is turned by either the tire removal tool or a specialized handle supplied with the jack. Larger vehicles, including many trucks, will be outfitted with a specialized high-lifting jack featuring a large base plate, a tall shaft with large teeth, and a ratcheting mechanism used to raise the vehicle. Another popular after-market car jack type is the hydraulic jack. A small hydraulic jack can lift can either be a upright non-wheeled model, or a horizontal storage wheeled version. Finally, many automotive shops use a large floor jack that rolls under the vehicle and uses hydraulic fluid. These large floor jacks are capable of lifting the entire end of a vehicle when used appropriately.
- All jacks have safety features to protect the user from accidental injury. Wide bases help to stabilize a jack and prevent tilting or sinking into soft soil. Most car jacks also come equipped with their own handle or cranking mechanism, but alternately many of these also will accept the flat end of a tire tool to jack up a vehicle. When in the extended position, jacks will have a stop point that prevents the user from overextending the jack beyond its rated capabilities. When in the contracted position, jacks that are provided by the manufacturer will have a storage area specially formed or designed for the jack to rest in when not in use.
- Equipping motorists with car jacks has provided many benefits to those who are on the road. Most importantly, jacks have equipped drivers with the ability to change a tire in an emergency situation without having to call for assistance, which can save service fees and potential towing fees as well. Car jacks also provide the home auto enthusiast with a tool to use in maintenance of their own vehicle with the simpler tasks such as changing brake pads, oil and belts. When used appropriately with safety in mind, car jacks are an essential resource for anyone owning or operating a motorized vehicle.
- Safety should always be taken into consideration when operating any kind of jack. Jacks should always be placed on level ground and in an upright position. Car jacks should always be placed directly under a portion of the car frame, never under any body parts or other equipment. Safety mechanisms should always be utilized in accordance with the manufacturer's recommendations. When jacking up a vehicle, the parking brake should be applied and the wheels on the opposite end of the jack should be chocked in place to prevent rolling. Car jacks should never be used to support a vehicle overnight or for extended periods of time.
