Lifting a truck can be done in many different ways, and one of the easiest methods is to add a leaf spring. Adding a leaf spring will usually give you at least an inch or two of lift, while increasing the maximum load capacity.
Place the jack underneath the differential of the rear axle and lift the vehicle into the air. Place jack stands underneath the axle and the frame, so that both sides of the axle and frame are supported in the air. Keep the jack underneath the differential, but lower it down so the frame and axle are on the jack stands. Make sure it is completely secure before you crawl underneath.
Remove the rear wheels with a 1/2-inch ratchet and socket set. Place them to the side so that they are out of the way of your work space.
Use a 1/2-inch ratchet to undo the four nuts that secure the u-bolts to the axle on each side. Loosen them, but do not take them off completely. You don't want to release the tension from the leaf springs, so be careful.
Repeat the process on the other side, following the same steps. At this point, the springs should have no extra tension on them, but be sure to have everything resting on jack stands before you loosen the bolts any further. If the springs appear to be under tension, adjust the jack and jack stands as necessary to relieve the tension. This may involve lifting the axle up higher and resetting the stands, or dropping it lower and resetting.
Unbolt the u-bolts completely from the axle. It should now sit completely onto the jack stands with the jack supporting the differential and keeping it from dropping forward with the driveshaft.
Find the straps on either end of the leaf spring and loosen them by prying them with the pry bar. Don't distort them too much, as you'll be using them again.
Locate the bolt on the center of the leaf spring and loosen it. The spring pack should come apart at this point, allowing you to add your extra leaf spring.
Place the new leaf spring in the leaf spring pack, following the same arch as the original springs. Some add-a-leaf kits are placed at the bottom of the spring pack, while others are in the middle of the pack. Determine which one your model is via the instructions included with your kit.
Place the longer bolt provided with the kit through the new leaf spring pack. Tighten the bolt and reinstall the clamps as they were installed by the factory.
Jack up the axle and locate the hole on the axle pad onto the bolt on the leaf spring. Loosely bolt the u-bolts back into place in the same configuration as before.
Tighten the u-bolts down and lower the vehicle back to the ground.
