Decided to start diagnosing a hissing sound in the interior my 97 e300 diesel; everytime I would go left, I got the noise, everytime I went right, it got real quiet. Straight ahead, low speed it hissed kind of. Took off all belly pans, and it was immediately obvious. The rubber dust boot between the steering column and the firewall was completely torn in two and disintegrated. Makes sense. Now fellow w210 diesel (and non-diesel) enthusiasts, what is this part called and how do I replace it without disassembling the steering column somewhere to slip it on. Did the standard catalog searches, even Rusty's and I can't find a reference to it. Dealer item only? Thanks! It's amazing all the problems you find (catch) looking under the car.