Before jacking up the vehicle, place chocks under the wheels or otherwise block them to prevent the vehicle from rolling. Having raised the car with a jack to the desired height, it is necessary to install it on stands, placing them in places specially designed for this. Only after that you can start working. All of the above work must be done on a level surface.
When dismantling heavy units, such as an engine or gearbox, be careful not to lose balance or drop the unit. In addition, the machine must not be struck against adjacent parts, in particular the brake lines and brake master cylinder.