I have a 2004 Envoy XUV model. The back end seems to sit low when the vehicle sits for about 4 hours or more. Once the ignition is turned forward the compressor turns on and raises the truck. What does this mean? Also does this present a hazard to driving and what is my best to worst case scenario and the cost associated with it. Thank you.
There is a service bulletin on this type of condition and I listed part of the bulletin below because it is too long to list the whole bulletin.
If you need the entire bulletin you can get it at ALLDATAdiy.com
There also could be a small air leak that just may be a cracked line, air line seal, and a leak at the shock itself.
Cost could vary to a small amount to diagnostic time and the part (s) itself.
There shouldn't be any safety issues as long as you are not towing anything.
See if this information helps you; let us know how you make out.
Slow leaks could be hard to find and probably should be diagnosed at your local GMC dealer.
Date: November 27, 2006
Information for Diagnosis and Repair of Rear Air Suspension (RPO G67)
2004-2007 Buick Rainier
2006-2007 Chevrolet TrailBlazer SS
2002-2007 GMC Envoy, Envoy XL
2004-2005 GMC Envoy XUV
2002-2004 Oldsmobile Bravada
2005-2007 Saab 9-7X
The purpose of this bulletin is to provide information for diagnosis and repair of the rear air suspension (RPO G67).
Diagnostic and Repair Tips for Rear Suspension Sagging or Vehicle Sitting Low in Rear Customer comments on the rear suspension sagging or the vehicle sitting low in the rear (i.e., the vehicle has a nose-up attitude when parked) may be caused by the air compressor's 8-way electrical connector, which may not be fully locked into position. This may potentially cause an intermittent operating condition.
Use of the accessory inflator (refer to Accessory Inflator in the appropriate Owner's Manual) with the ignition key turned to the ON position can result in a temporarily inoperative condition if the air suspension attempts to raise the rear of the vehicle. If this occurs, a RUN/OFF key cycle is necessary to reset the compressor. To avoid these conditions, only use the auxiliary inflator when the ignition key is OFF. In addition, when the auxiliary inflator is in use, it will time out after 5 minutes and must be allowed to cool off before continued operation can begin again.