Two locations Terry mentions are on our list of good wash places too: Truck-o-Mat (most any of them) and the new wash opposite the Flying J in Knoxville. We've also had great work done at:
Phoenix: Danny's Big Rig Resort across the street from the Flying J.
Kingman, AZ: Freedom Truck Wash, I-40, westbound side, on top of the hill before you reach Kingman, next to Love's.
Albert Lea, MN: TA, Exit 11, I-35, near the I-35 and I-90 interchange.
Little Sisters truck washes, any of them.