37' is the turning DIAMETER. I have two W211 Mercedes E500s. One RWD, the other AWD. My 85D turning circle appears to slot in closer to the AWD. I need to swing a little wider to make the 180 turn into the parking space I use at work vs. what I needed with the RWD, about the same as the AWD when I would take it. One of the reasons the 85D was an easy decision.