2002-2009 GMC Envoy Rear Air Suspension Conversion Kit (GB1R0)

Replaced Components
The 2002-2009 GMC Envoy is built with the following rear suspension components:

2002-2009 GMC Envoy Air Springs (x2) - commonly referred to as air bags, a plastic and rubber bag that uses pressurized air as a cushion to support the weight of the vehicle. These rubber air springs are the number one cause of all air suspension leaks. Since all air springs all go bad at about the same rate, if one is leaking, the others will not be far behind. For a proper repair, all of them need to be replaced at the same time.

2002-2009 GMC Envoy Shock Absorbers (x2) - has metal tubing filled with gas-charged hydraulic fluid in order to reduce or dampen vibration and bounciness caused by travel on a rough surfaces. Some models dampening may be controlled by the suspension control module and can be very costly to replace.

2002-2009 GMC Envoy Height Sensors (x2) - a linkage located near each wheel of a vehicle with any electronic suspension that, either mechanically or electronically, constantly measures the height of the vehicle, and reports this information back to the control module so that the computer can identify if changes in height need to be adjusted accordingly. The ride height sensor is a moving part, and like all moving parts, they will eventually wear out.

2002-2009 GMC Envoy Air Lines- tubes that run from a compressor to the air which carry pressurized air to the air springs in order to adjust the height of the vehicle, respectively.

2002-2009 GMC Envoy Solenoids (x2) - usually L-shaped, these plastic components connect the electrical connection and lines of suspension components to the suspension control module on vehicles with active suspension. The solenoid regulates the air pressure for each air spring. Solenoids start to leak as they wear out causing the vehicle to sag or to lean. This will cause the ride height sensor to send a signal to activate the compressor in an attempt to inflate the air suspension and level out the vehicle. This excessive work load will eventually lead to total failure of the compressor.

2002-2009 GMC Envoy Compressor Assembly- creates/sends pressurized to active suspension components. When the air suspension starts leaking, the compressor/pump starts working harder to try to keep the system inflated. By the time air suspension leaks down completely, sitting the vehicle on its tires, the compressor will either have failed or be well on its way to full failure. Buying replacement air springs and taking the time to install them only to find out the compressor still needs to be replaced can be very frustrating, time-consuming, and expensive.

2002-2009 GMC Envoy Dryer- prevents moisture build-up inside of air suspension parts.

2002-2009 GMC Envoy Suspension Control Module- a computer which is responsible for the operations of the air suspension system and maintaining the vehicle's correct ride height.

2002-2009 GMC Envoy O-rings- Although they are the least expensive parts of the air suspension, they are responsible for maintaining the seal where all of the air lines connect. Be sure to replace the O-rings when repairing any air suspension system.



Suspension Failure Signs
If the 02-09 GMC Envoy is not meeting and maintaining its proper ride height, a bad suspension may be to blame. Look for these signs of a failed or leaking air suspension before it’s too late and total failure sets in. The most noticeable is a sudden drop or squatting of three to five inches in the rear of the vehicle. A lean from one side to the other could be present. Other components may wear out, too. The air compressor, for example, may stop working or may run too often (in this case it is loud and noisy). Lastly, an illuminated suspension warning light on the dashboard is an obvious red flag for suspension trouble. If any of these symptoms are present, get the suspension fixed promptly.

OEM Replacement Cost
'+ Air Springs ($200/air spring)
+ Compressor and Dryer Assembly ($500)
= Over $900 (but that doesn't include replacing electronic components that are known to fail such as the height sensors).

Aftermarket Replacement Cost
'+ Air Springs ($190/pair)
+ Compressor and Dryer Assembly ($500)
= Over $600 (but that doesn't include replacing electronic components that are known to fail such as the height sensors).