Got a Roadmaster M chassis I just noticed a horn sound coming from the driver side wheel. It appears at low speed <25mph it occurs on speed bumps and slight dips in the road, but not constantly. It might be there at highway speed but with all the squeaks and rattling I can’t tell. My guess is either shock or air bag, both look good to me. I’m obviously going to have it looked at in the near future. Any thoughts on what it could be? To save money on the mechanic what should I have him specifically look for? As always thanks for your time.