HI Forum, I'm new to the MB world first post and not too familiar with MB. I've got put plenty hours under on my FCar.
I've taken over a 2007 GL450 from a family member with 164,000 miles and it seems that every time it comes out of the shop it goes back in. I currently have 2 questions for the Forum.

1. I noticed a knock on the RH front wheel when hitting road side bumps. It is not obvious driving down the Highway. Also it only happens while the Air ride system is on the lowest level 1. When I raise the Car to Level 2 or 3 it goes away. Has anyone had this experience with such a thing? I see the forum talks about sway bars and ball joints and other problems.
2. The SRS light for side curtain is always on. Can I reset this with a computer connection?

The Dealership In SLC that has done the work in the past can't get the vehicle in until Feb and it came out of the shop 2 months ago and has 100 miles on it since. With forum experience, can anyone advise on what test I can do to pinpoint sway bar, ball joint or anything else? Seems like this model MB has lots of wheel problems. What I've read in the MB forum seems like dealers say it is one thing then you fix it and it actually something else, with alot of money spent just to trouble shoot a problem. I appreciate the advice and direction. Cheers, crash