Your vehicle was supplied with a jack for emergency road repairs. This jack is fine for changing a flat tire or other short term procedures not requiring you to go beneath the vehicle. If it is used in an emergency situation, carefully follow the instructions provided either with the jack or in your owner's manual. Do not attempt to use the jack on any portions of the vehicle other than specified by the vehicle manufacturer. Always block the diagonally opposite wheel when using a jack.
Using a garage floor jack, or heavy-duty hydraulic unit, jack a Ford truck from under the axles, radius arms, or spring hangers and the frame. Be sure and block the diagonally opposite wheel. Place jackstands under the vehicle at the points mentioned or directly under the frame when you are going to work under the vehicle.
Never place the jack under the radiator, engine or transmission components. Severe and expensive damage will result when the jack is raised. Additionally, never jack under the floorpan or bodywork; the metal will deform.
Whenever you plan to work under the vehicle, you must support it on jackstands or ramps. Never use cinder blocks or stacks of wood to support the vehicle, even if you're only going to be under it for a few minutes. Never crawl under the vehicle when it is supported only by the tire-changing jack or other floor jack.
Small hydraulic, screw, or scissors jacks are satisfactory for raising the vehicle. Drive-on trestles or ramps are also a handy and safe way to both raise and support the vehicle. Be careful though, some ramps may be too steep to drive your vehicle onto without scraping the front bottom panels. Never support the vehicle on any suspension member (unless specifically instructed to do so by a repair manual) or by an underbody panel.
It is very important to be careful about running the engine, on vehicles equipped with limited slip differentials, while the vehicle is up on the jack. This is because when the drive train is engaged, power is transmitted to the wheel with the best traction and the vehicle will drive off the jack if one drive wheel is in contact with the floor, resulting in possible damage or injury.