When I bought it the Allroad already had an Arnott coilover kit installed. The part number I have for the pass side Bilstein shock is C-2130-R.

It's my wife's car so I'm not extremely familiar with it. I drove it a few days ago and it seemed like a tire was way out of balance or even out of round on the rear pass side... the tires only have maybe 1000 miles on them. Maybe it was the tire causing the shake maybe not, it disintegrated yesterday on her while she was driving to work... sidewall is gone. Before the tires were replaced it had the same issue, not as bad as now but similar... the old tires were getting pretty worn so we put new ones on and I thought that would fix the shake... guess not.

Now I've got 4 new tires on the way but I have started suspecting that the rear coilovers might be bad. A theory I had was that the shake the car was getting was because the shocks were bad, and the continuous shake was causing fatigue on the sidewall which caused it to blow. So I pulled the shocks tonight kinda hoping for an obvious answer and I didn't get one...if I put 60-65lbs of my weight on the shock it goes down, then when I release it and it goes back up... exactly what they're supposed to do. I'm just wondering if they are supposed to have more resistance than that though. 65lbs of force didn't seem like enough but I don't know.

Since I already have the coils and everything else that came with the kit and just need the shock, is there a way I can buy just the shock somewhere, like Napa or Car Quest? or are these shocks custom made for this conversion? I was hoping to buy another shock and test that against mine to help eliminate some theories.