Removal & Installation
Low pressure gas shocks are charged with Nitrogen gas. Do not attempt to open, puncture or apply heat to them. Prior to installing a new shock absorber, hold it upright and extend it fully. Invert it and fully compress and extend it at least 3 times. This will bleed trapped air.
- Raise the front of the vehicle and place jackstands under the lower control arms. Ensure that the lower shock attaching nuts do not become obstructed by the jackstands.
- Remove the upper shock-to-frame attaching nut, washer and insulator assembly.
- Remove the two lower shock-to-control arm attaching nuts.
- Slightly compress the shock absorber by hand and remove it from the vehicle.
- Position the lower washer and insulator on the shock absorber rod and position the shock absorber to the upper frame bracket mount.
- Position the upper insulator and washer on the shock absorber rod and install the attaching nut loosely.
- Position the lower shock absorber mounting studs into the control arm and install the attaching nuts loosely.
- Tighten the lower shock attaching nuts to 15-21 ft. lbs. (21-29 Nm), and the upper shock attaching bolts to 30-40 ft. lbs. (40-55 Nm).
- Before servicing the vehicle, refer to the Precautions section.
Remove or disconnect the following:
Negative battery cable
Install or connect the following:
Position the lower washer and insulator on the shock absorber rod and position the shock absorber to the upper frame bracket mount
Testing & Inspection
The purpose of the shock absorber is simply to limit the motion of the spring during compression and rebound cycles. If the vehicle is not equipped with these motion dampers, the up and down motion would multiply until the vehicle was alternately trying to leap off the ground and to pound itself into the pavement.
Countrary to popular rumor, the shocks do not affect the ride height of the vehicle. This is controlled by other suspension components such as springs and tires. Worn shock absorbers can affect handling; if the front of the vehicle is rising or falling excessively, the "footprint" of the tires changes on the pavement and steering is affected.
The simplest test of the shock absorber is simply push down on one corner of the unladen vehicle and release it. Observe the motion of the body as it is released. In most cases, it will come up beyond it original rest position, dip back below it and settle quickly to rest. This shows that the damper is controlling the spring action. Any tendency to excessive pitch (up-and-down) motion or failure to return to rest within 2-3 cycles is a sign of poor function within the shock absorber. Oil-filled shocks may have a light film of oil around the seal, resulting from normal breathing and air exchange. This should NOT be taken as a sign of failure, but any sign of thick or running oil definitely indicates failure. Gas filled shocks may also show some film at the shaft; if the gas has leaked out, the shock will have almost no resistance to motion.
While each shock absorber can be replaced individually, it is recommended that they be changed as a pair (both front or both rear) to maintain equal response on both sides of the vehicle. Chances are quite good that if one has failed, its mate is weak also.