90027C Conversion Kit
Replacement of Front Strut and Rear Air Shock

This kit replaces the front electronic and rear electronic air shock absorbers on the vehicles listed above, replacing them with front passive strut assemblies and rear coil springs and conventional shock absorbers. The resistors in this kit are designed to replace the non-operational electronic circuit within the shocks and struts. This kit will eliminate the rear air shocks replacing them with heavy duty coil springs and conventional shock absorbers. Note: If the air leveling system is still operational you can retain the leveling functionality while eliminating the electronic dampers by using Monroe conversion kit 90026C in place of 90027C.

The installation of the provided resistor(s) will maintain the electrical circuit to eliminate most “service ride control” messages, provided that the warning is caused by the electronics within the shocks and struts.

Note: This kit will not eliminate suspension warning messages caused by issues with the air leveling system. If the service suspension message appears it will have to be reset each time the vehicle is started. The message is a minor nuisance which does not affect the operation of the vehicle after the conversion is completed.

• Two front strut assemblies.
• Two heavy duty coil springs.
• Two premium shock absorbers.
• Four parts packages with resistors.
• Instruction Sheet.

1. Raise vehicle by frame at proper lift points. Consult GM Owner Manual if necessary and make sure the vehicle is properly supported.
2. Remove the front wheels.
3. Support the lower control arm and remove the two lower strut mounting bolts.
4. Disconnect the electrical connector that is attached to the top of the strut rod.

5. Remove the three (3) upper mounting nuts and remove the strut assembly. Note: You may need to disconnect the outer tie rod from the steering knuckle to provide more clearance for removal.
6. Repeat steps 3-5 on opposite side of the vehicle.
7. Install the new strut/coil spring assembly and loosely attach the three (3) upper mounting nuts. Pivot the lower control arm up into place and attach the lower mounting bolts “hand tight”.
8. If the outer tie-rod end was disconnected from the steering knuckle during step 5, reinstall and torque to 44 lb-ft (60 Nm). Warning: Inspect and replace worn components/ fasteners, if necessary.
9. Repeat steps 7-8 on opposite side of the vehicle.
10. Reinstall the front wheels and lower the vehicle so its full weight is on the suspension and tighten the lug nuts to 140 lb- ft (190 Nm). Then tighten the upper mounting nuts to 37 lb-ft (50.2 Nm).
11. Next tighten the two strut assembly lower mounting bolts to 37 lb-ft (50.2 Nm).
12. To eliminate the electronic suspension, the electrical connectors will now need to have a resistor installed (provided). Refer to the instructions within the resistor parts package for this installation.

1. Raise vehicle by frame at proper lift points. Consult GM Owner Manual if necessary and make sure the vehicle is properly supported.
2. Disconnect the ABS wire from the frame.

3. Disconnect the vent hose at the top of the differential.

4. Remove the bolt that holds the brake line bracket to the rear differential.

5. Disconnect one end (upper or lower) of each of the rear anti-sway bar end links. Save hardware for reuse.

6. Remove the bolt holding the parking brake cable bracket to the frame. Save hardware for reuse.

7. Disconnect the electrical connector for the electronic ride control from upper shock mount. Disconnect the air line from the shock by separating the clip and pull straight out from the fitting.

8. Support the axle with a floor jack or adjustable stands. Remove the air shocks by disconnecting the upper and lower mounting hardware. Save hardware for reuse.
9. Using the floor jack or adjustable stands, slowly lower the axle down to remove the coil springs. You will have to lower the axle further to install the new coil springs. Caution: Do not strain the brake hoses by overextending the axle.

1. Install new coil springs, reusing the OE upper and lower spring isolators (replace if necessary). Orient the springs so the label is closer to the TOP making sure both pigtails are secure within the spring seats. Rotate the spring so the lower pigtail is parallel with the axle.

2. Carefully raise the rear axle while ensuring the upper coils remain properly seated in the upper spring seats. Caution: Take care that vehicle weight does not shift off of frame supporting points when lifting the axle.
3. Install new shock absorbers into the upper mounting brackets using the original hardware (inspect and replace if necessary). Hand tighten only.
4. Continue to raise the axle until the lower shock mounts align with the lower mounting brackets. Reinstall original mounting hardware (inspect and replace if necessary). Hand tighten only.
5. Reconnect the vent hose and brake line bracket to the differential and tighten securely.
6. Reconnect the parking brake cable bracket to the frame and tighten securely.
7. Reconnect the rear anti-sway bar end link. Reusing the original mounting hardware torque the upper to 55 lb-ft (75 N∙m) and the lower to 107 lb-ft (145 N∙m) (inspect and replace if necessary).
8. Reattach and secure wheel speed sensor wires into the clips on the frame.
9. Lower the vehicle so the full weight is resting on the tires and jounce the suspension. Then torque the upper and lower shock mounting hardware to 70 lb-ft (95 N∙m).
10. To eliminate the electronic suspension, the electrical connectors will now need to have a resistor installed (provided). Refer to the instructions within the resistor parts package for this installation.