Used to raise the body of an off-road vehicle, coil spring spacers are a great way to gain a couple inches of altitude without replacing the springs. Though most people who purchase coil springs spacers have probably already installed some sort of lift kit, many use spring spacers as a fine tuning tool to augment the kit's stock ride height. This gives even those who buy fixed height kits to adjust for the proper amount of clearance without having to purchase new springs.
Loosen the wheel's lug nuts while vehicle is still on ground. If using a floor jack, only loosen one wheel at a time. Loosening the lug nuts on all wheels can cause damage to the studs on the opposing side when the vehicle tilts away from the jack.
Raise vehicle with either a large floor jack or frame lift. Make sure to utilise the factory lift pads to avoid damaging components or lines. Do not place jack on axle, since the suspension needs to swing free.
Place jack-stands under the frame to support it and lower vehicle onto them onto them. You will need the jack to raise the axle when you put everything back together.
Place jack under the axle and raise it until it's bearing some weight. This will prevent damage to suspension components when the axle is hanging free.
Make sure the axle is firmly supported by the jack, as damage may occur to other components if it slips.
Unbolt the shock absorbers from the axle. Some find it more convenient to unbolt the shocks from the frame, but generally it's best to have them hanging out of the way under the vehicle.
Remove the cottar pin from the sway bar nut, if so equipped.
Unscrew the castle nut from the sway bar end link.
Use ball-joint separation tool and hammer to remove the sway bar link, if required. Generally, the link will come off with the tap of a hammer.
Use spring compressor to secure spring before loosening any components. Make sure the spring compressor is secure on the coils, or severe injury may result. You may have to unbolt the coil spring retainers from one or both sides of the coil spring before compression, depending on the make and model.
Lower axle as far as it will go without falling off the jack.
Insert coil spacer on top of spring.
Raise the jack very gently until coil spring/spacer assembly contacts both axle and frame in proper location. If you need to hold the spacer in place while mounting, grasp it around the sides, and never near the top. This will greatly reduce the risk of injury of the compressor fails during installation.
Re-attach coil spring retainers once you are able to do so. Make sure the axle is bearing the weight of the frame.
Reassemble everything in the reverse order of disassembly, and repeat procedure on other side.
Never use homemade coil-spring spacers.
Retail spacers are engineered and tested to withstand the extreme side loading experienced by these items, whereas home-made units often fail with the strain. Spacer failure can lead to a catastrophic accident, especially if trail riding produces stress fractures which do not fail immediately, but rather under the high-speed harmonic vibration of freeway travel.