Air Suspension Problem

[scotd1]

I have a 2004 GX470 that has started making an annoying noise. It is the air compressor for the leveling system that turns on at random times. It cycles on when you first start it and then several times in a 15 minute drive. We have had this vehicle since new and just noticed it starting to do this a month or so ago, before that we rarely ever heard it. Is it a leak in the air shock/strut, lines or maybe the compressor it self? I have not taken it to the dealer as I'm sure they will come up with a high dollar cure for what ever it is.

I would appreciate hearing from anyone with knowledge and/or experience on this.

Thanks.

Don (first time poster)

[mann777]

It is normal for GX models on start up and at Ign off stats - The compressor begins to work and the self leveller begin to adjust the suspension, and at off they tend to lower down. Nothing abnormal and it is how the Automatic Suspension works.

Now to the problems you have quoted , There are various problems to the rear suspension. The various factors are you should look at is if the vehicle bottoms out, or does it pull to the side while drive and due to the tire wear and tear, there is a tendency of mis-alignment. And most important if the shocks are worn out, and wheel being out of balance. Make a check to all these areas and correct as neccessary.

Now if all of the above is ok, do a visual vehicle inspection.

1. Rear Shock Absorbers ( view from the rear tire wheel well side of both RH/LH side and check for any leaks.

2. Go to the rear of the vehicle and check underneath to the left of the vehicle suspension area, you will see the Pneumatic Cylinder Assy. Check for any leak around the area. If it is Ok then check the sensors by jacking up the vehicle. Ensure to s/w off the Ride hieght Mode to off at the driver area. Now the Sensors are situated below the Upper Control Arm Assy. Most of the times these do tend to become faulty and the compressor behave abnormal at times.

They are not expensive to replace, The dealers rip you off with the manhours involved. You could replace this by doing in your own garage. To chek the sensors faulty. all you can do is goto autozone and have a test done thru a scan tool. cheers