1997-1998 Ford E350 Econoline Base 6.8L V10. 1997-1998 Ford E350 Econoline XL 6.8L V10. Notes: Engine Coolant Thermostat Housing Assembly -- Start to Open Temperature: 85?. Detailed Notes: Engine Coolant Thermostat for Ford F-250 F-350 Super Duty E-350 Super Duty 85.