Jack Stands
Mechanical supports placed under a raised vehicle's frame to hold it safely in place during under-car repairs.
Jack stands are mechanical support devices designed to hold a vehicle in a raised position after it has been lifted with a hydraulic floor jack. While a floor jack is used to lift the vehicle, it relies on hydraulic pressure which can fail suddenly and catastrophically. Jack stands provide a solid, mechanical metal lock that eliminates the risk of the vehicle falling, ensuring the safety of the technician working underneath.
Jack stands are constructed of heavy-duty steel or cast iron and are rated by weight capacity, typically ranging from 2 tons to 12 tons or more. They feature adjustable columns with a ratcheting mechanism or locking pins to set the desired height. Mating the stands with the vehicle's designated frame lift points or solid axle tubes is crucial to prevent slipping or damaging the chassis.
When using jack stands, the vehicle must be parked on flat, solid ground, and the wheels remaining on the ground must be chocked. Once the vehicle is lowered onto the stands, it is standard safety practice to give the vehicle a firm shake to ensure it is completely stable before crawling underneath.