The HVFC was alerted @1649 hrs for a working vehicle fire with multiple calls reported to be in the area of Tractor Supply on Jandy Blvd. Engine 5311 responded with a crew of 3 within minutes of the initial dispatch. While enroute Asst Chief 5053 (F50) arrived on scene and confirmed a fully involved working car fire and advised county that the call was on Rt248 west of Jandy Blvd in Nazareth Borough and added fire 50 to the call. Engine 5311 arrived on scene and the crew streched 1 - 1 3/4" line from the bumper and extinguished the fire within minutes of arrival. 5011 arrived and assisted with overhaul. Rt.248 was shut down in both directions while crews worked and all F53 units were clear within an hour.