I have an 08 LTZ burb and about every 3 starts, there's a noise that comes from the driver side rear quarter panel. Sounds the same as when the automatic liftgate is coming down. Of course, it won't do it at the dealership when I try to have the tech guys listen to it. Anyone have any ideas? The sound lasts for about 5 seconds and sounds like a small motor/servo of some type. I can't seem to find any diagrams about what kind of motor or servo would be in the driver rear quarterpanel, but my guesses are 1. autolift captain chair 2nd row, 2. the power liftgate, or 3. the air ride suspension. Pls help!

 

I don't know for sure, but my guess it is the air suspension leveling the rear of the vehicle. I have had a 2005, 2007 and now a 2009 and all have that motor sound when you start the vechicle on occasions. To see if this really is the sound you are inquiring about, load some weight in the back of the vehicle and turn on the key. The vehicle should start a compressor in the rear to level the vehicle...you should hear the sound.The leveler does not start until you turn on the key.

Good Luck.

 

Have the same "motor" noise in my 08 LT. Sounds like its in the dash.

 

suburbans dont have air suspension

 

jbar is right, i_keyser is wrong, the LTZ comes standard with "autoride" self-leveling suspension. When you hook up a trailer or load weight in the back a small compressor kicks on and inflates the air shocks to level the vehicle. If you hear this every time you may have a small leak in the system since I rarely hear mine unless I have hooked up my trailer or have a car full of people. Hope this answers your question.