This diesel exhaust fluid (DEF) filler cap is designed to match the fit and function of the original cap on specified vehicles, and is engineered for durability and reliable performance. This part is compatible with the following vehicles. Before purchasing, enter your vehicle trim in the garage tool to confirm fitment. [Kenworth C500: 2010, 2011, 2012, 2013, 2014, 2015, 2016] - [Kenworth T2000: 2010, 2011] - [Kenworth T660: 2010, 2011, 2012, 2013, 2014, 2015, 2016] - [Kenworth T680: 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021] - [Kenworth T800: 2010] - [Kenworth W900: 2010, 2011, 2012] - [Peterbilt 210: 2010, 2011, 2012, 2013, 2014, 2015] - [Peterbilt 320: 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018] - [Peterbilt 330: 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021] - [Peterbilt 335: 2010] - [Peterbilt 337: 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022] - [Peterbilt 362: 2010] - [Peterbilt 365: 2010, 2011, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022] - [Peterbilt 384: 2010, 2011, 2012, 2013, 2014, 2015, 2016] - [Peterbilt 387: 2010, 2011] - [Peterbilt 388: 2010]