This vehicle is equipped with engine speed sensitive power steering. Firmer at speed and more boost when slower. I haven't noticed a problem in my 2009 35d. I previously drove a MB E350 and had a malfunction with the speed sensitive steering (dead battery, then jumped to start). Steering a low speed was like steering an older vehicle without power steering, really like driving a truck. Once battery charged and cycled ignition, problem was gone.

If you have an issue with this system, you could end up with a high steering effort condition in a parking lot. Perhaps you could stop by a dealer and drive one of their vehicles around the lot for comparison. If you have a problem, it should be obvious. Let us know how it goes.