Don't bother with the Mercedes cross bars. They won't be strong enough to carry anything anyway. The
Yakima Lowrider roof rack system will fit your benz perfectly and is simple to install. The Yakima Racks Lowrider system is a multi-purpose base rack that attaches directly to your Mercedes Benz car rack side rails, creating a system that can handle the load capacity of bikes, skis/snowboards, kayaks, canoe, surfboards, cargo and luggage etc. The Lowrider base rack system includes four Yakima Lowrider towers that clamp right onto your side rails and a pair of Yakima cross bars that connect to the four Lowrider towers. The various gear carriers will attach directly to the Lowrider front and rear cross bars. The 48 inch cross bars are the recommended length for your mercedes rooftop too. Then you can mount any of Yakima Racks gear carriers right to those Lowrider crossbars as well.