Car-X Auto Service 7500 W Layton Ave, Greenfield, WI53220 Founded in 1971 as primarily exhaust system specialists, Car-X Auto Service has since expanded to provide full repair…More and maintenance services. Let the friendly mechanics at this Greenfield Car-X location expertly care for your vehicle. A waiting area is available to customers, as well as several restaurants and stores within walking distance. Visit the Car-X website to print out money-saving coupons. In addition, you can sign up to receive monthly coupons on a regular basis. Ask about the "Life Plus" brake guarantee when you visit the shop.