We have been trying to clean tire marks off of this large driveway made up of unfilled travertine pavers. What has helped so far is adding a couple of ounces of delemonine to our solution. I was just wondering, prior to using our spinner, if we prescrubbed with our 175, if we should use a pad or a brush under the 175 and if so which type of pad or brush? If anyone has used one or the other successfully I would really appreciate your help.