Rear Air Bag Suspension To Coil Spring Suspension Conversion Kit Installation Instructions For The Following Vehicles:
Chevrolet Trailblazer 2002 – 2009
GMC Envoy 2002 – 2009
Chevrolet Trailblazer EXT 2002 – 2006
GMC Envoy ESV 2002 – 2006
CAUTION: Working with coil springs can be dangerous, Follow all instructions carefully. Use EXTREME caution when working around compressed coil springs. If you do not feel comfortable handling this job, we recommend you bring it to a trusted repair shop.
Removal of air springs:
1) Support vehicle in air, the rear suspension MUST be fully extended, in other words hanging freely with no supports under it, to do this, be sure the vehicle is supported by the FRAME and not the rear differential or control arms.
2) Remove both rear wheels
3) Locate the air suspension compressor located behind the passenger rear wheel.
4) Unbolt the compressor bracket and lift upwards to unhook it from the frame.
5) Release the air pressure from the air springs by disconnecting the air lines going to the compressor.
6) Disconnect the electrical connectors from the compressor and set aside. The compressor assembly will not be reinstalled.
7) Release the top of the rear air-springs, there is a locking tab that must be depressed while you turn the top of the air-spring to unclip it from the mounting bracket. Some models have a small hole in top of the mounting bracket to access the locking tab.
8 ) Once air-spring is released, remove the air line by pressing down on the steel fitting going into the air-spring and pulling out on the air line at the same time and remove the air-springs from the vehicle.
9) Remove both lower shock bolts. This will allow the axle to hang freely on the control arms.
Installation of coil springs:
1) With the rear differential hanging freely, place the new coil springs on the spring perches.
2) With a floor jack, CAREFULLY jack up the rear axle below the differential housing (pumpkin) until the holes for the shocks align with the hole in the rear differential shock bracket.
3) Install the bolts for the shock absorbers and tighten the shock nuts to 70 ft/lb.
4) Reinstall the wheel assemblies, lower vehicle, and torque the lug-nuts to 100 ft/lb
Disabling the Air-Suspension System:
As long as the air suspension compressor remains disconnected, you will not have any warning lights or malfunctions due to the coil spring conversion.