The sway bar end link joints may wear and cause a knocking noise over bumps. Loose or warn links should be replaced to correct this type of noise.
Car Problem Reports
Mercedes-Benz CLK350 Worn Sway Bar Link Joints Causing Knocking Over Bumps
Mercedes-Benz CLK350 Problem
Average Mileage: 94,000 mi (78,000 mi - 110,000 mi)
Visitor, 2006 Mercedes-Benz CLK350, 110,000 mi
Knocking sound as I am braking over bumpy road. Not fixed yet.
Visitor, 2006 Mercedes-Benz CLK350, 78,000 mi
Knocking sound from front offside wheel arch area when going over bumps.
Solution....sell car....have spent a fortune on repairs over last few months