A guy at the Bonneville Salt Flats specifically recommended Blue Beacon, saying they would get the salt out of the wheelwells and underneath. I did opt for the "Undercarriage Rinse". I had already self-washed my car at a wand-style car wash. Bottom line: after Blue Beacon, I was $27.25 poorer, and I couldn't tell the difference. I waited over an hour in line for this??? I later found a LOT of salt in various nooks and crannies on the car. The only reason I'm not giving a lower score is because I recognize that this is a truck wash.