My 85 300sd started to slightly pull to the right(front pass wheel) about a month ago, I bought it about 2-3 months ago. It pulled progessively harder and started vibrating from 65-70 mph. You could raise/lower speed to eliminate the vibration, for a couple weeks. Last weekend I drove about 90 mi, up to 80 mph - to eliminate the vibration, it started pulling a lot harder to the right, like a flat tire. Since I bought it, tire pressure is constantly even at 30-35 psi. In the last 10 mi before I got home, it felt like the lug bolts were loose, not the case (very violent shaking down to 10 mph). I installed the early model spare - the bolts are too short for it, I have late model rims. Installed idler arm kit this morning, AND Bought a nice wheel/michelin tire at upullit as I needed a spare anyhow. as there was a huge ply separation on old passenger tire. Now it still shakes but not nearly as bad, front end seems tight now - tie rod ends, center link, probably try steering damper next. Any ideas?