Unfortunately black is notoriously hard to keep free of marring. Are you using the two bucket wash technique preferably with Grit Guards? One way to determine which towel is causing the marring is by washing the car using your wash mitt in one direction, and then drying the car in the opposite direction. Once you're done, inspect the car, and you should be able to tell which caused the marring.
2013 Sterling Grey V6 Premium - Ordered: 9/18/2012 Built: 10/09/2012 Arrived: 10/25/2012 Picked up: 10/27/2012
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