The factory DEF Heater on a wide range of Ford Super Duty trucks often fails from fluid intrusion. This Dorman OE FIX solution modifies the OEM design to address this failure point and increase reliability. This part is compatible with the following vehicles. Before purchasing, enter your vehicle trim in the garage tool to confirm fitment. [Ford F-250 Super Duty: 2011, 2012, 2013, 2014, 2015, 2016] - [Ford F-250: 2015] - [Ford F-350 Super Duty: 2011, 2012, 2013, 2014, 2015, 2016] - [Ford F-450 Super Duty: 2011, 2012, 2013, 2014, 2015, 2016]