Grinding noise at high speed.
Recently I started to notice an interesting grinding noise when I drive at 65mph on highway, when going over uneven surface. Like, the car jumps a little bit, and made a very quick and sharp grinding sound when sitting down.
Car is w205 c63s, running Zito 20 ZF01 in 20”. Currently only observed this in comfort suspension mode, and this noise is more likely to happen when I got passangers.
Initially I though it was the wheels, but the tiers and fenders do not have any sign of rubbing. Also the sound is more like a short metal grinding instead of rubber. The sound mostly come from the rear of the car.
I also have aftermarket IPE exhaust, but the muffler seems to be high enough it it’s impossible that it will touch the ground.
Anybody else experiencing this issue? Any thoughts on the likely cause and how should I investigate?
Thanks!
p.s here are two pics of the baby
Last edited by Jinggyjin; Sep 15, 2019 at 10:02 PM.







