A floor jack is one of the most essential tools in any shop, allowing you to lift a corner or end of a vehicle quickly. It uses a hydraulic cylinder operated by a pump handle to raise a metal lift saddle against a vehicle's frame or jack point. Most standard jacks feature a low profile to slide under sports cars and can lift between two and four tons. Never, under any circumstances, work under a car supported only by a floor jack. Hydraulics can fail instantly and without warning. Always lower the vehicle onto sturdy jack stands before placing any part of your body underneath.
Mechanic Glossary
Floor Jack
A hydraulic device used to lift vehicles off the ground for maintenance, tyre changes, or repairs.
Frequently Asked Questions
A 3-ton floor jack is usually plenty for most SUVs. While the vehicle may weigh 2 to 2.5 tons, you are only ever lifting half or a quarter of that weight at one time.
The release valve might not be fully closed, or the internal hydraulic seals are worn out and leaking fluid past the piston. Check the release valve first, and if it still sinks, rebuild or replace the jack.
Look at your owner's manual for the designated pinch welds or frame points. Placing the jack under body panels, floorboards, or oil pans will cause serious structural damage.
No, it is highly dangerous. Floor jacks need to roll slightly as they raise the vehicle. On soft or uneven surfaces, the jack can sink, tilt, or slip, dropping the car.