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Discussion Starter · #1 ·
I noticed some grinding noise when my foot is on the break pedal and air suspension is working to either raise or lower the height. To reproduce, put your foot on the break, start the car, leave your foot on the break and select Eco drive. Not sure if this has been mentioned by other drivers in the past, but it's quite normal to keep your foot on the break the whole time before you start to drive, particularly when the car requires it in order to start. I really love the AS because I have a handicap person in the household and AS makes it easy for her to enter and exit the car.
 

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Just wondering, why do you keep your foot on the brake after starting the car? You haven't moved out of park yet, so no need for the foot on the brake..
Get in, foot on brake, start car, release brake. Then do whatever adjustments I need. Don't you?

The car might move about a bit when lowering and rising with the air suspension, and with the brake active some noises might sounds?
 

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Discussion Starter · #3 ·
Just wondering, why do you keep your foot on the brake after starting the car? You haven't moved out of park yet, so no need for the foot on the brake..
Get in, foot on brake, start car, release brake. Then do whatever adjustments I need. Don't you?

The car might move about a bit when lowering and rising with the air suspension, and with the brake active some noises might sounds?
Guess I need to change my habit then.....
 

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Nothing wrong with it! Just... unnecessary, imho :)
 

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Sounds logic; the suspension springs are not perpendicular to the ground. Rather the front suspension springs (or cylinders with air suspension) are facing forward a bit.
Thus the suspension system forms a trapezium when seen from the side: like this /=|
If you raise the car, the front and rear wheels are moving away from each other just a bit, thus lengthening the wheelbase. And when you lower it, front and rear wheels are coming closer again.
When you are on the brakes, you are preventing the wheels from rolling to accommodate this movement.
 

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Guess I need to change my habit then.....
I often keep my foot on the brake after starting up, since it needs to be there to start...its actually two less steps than starting, moving the foot off the brake while I futz with the radio or whatever, then putting my foot back on when I need to shift out of park. I don't keep it there because its necessary but I don't move it because thats also not necessary.

Regarding the grinding noise, I can usually detect a slight noise when the air sus is adjusting but its not what I would describe as grinding. Sometimes I hear it from outside after parking, I think it self-levels right?
 

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Discussion Starter · #7 ·
I often keep my foot on the brake after starting up, since it needs to be there to start...its actually two less steps than starting, moving the foot off the brake while I futz with the radio or whatever, then putting my foot back on when I need to shift out of park. I don't keep it there because its necessary but I don't move it because thats also not necessary.

Regarding the grinding noise, I can usually detect a slight noise when the air sus is adjusting but its not what I would describe as grinding. Sometimes I hear it from outside after parking, I think it self-levels right?
I think you're referring to what sounds like electric motor working to lower or raise the suspension. I notice that too. But when I have my foot on the break, the grinding noise is so loud and I don't hear motor sound....
 

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Of course it's the brakes slipping as the suspension lowers and the wheels adjust to the different stress angles. Just lighten up the pressure on the brakes. Works for me.
 
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