Industrial Injection GM Common Rail Gorilla Girdle For 11-16 6.6L LML Duramax 14mm - PDM-0603714mm Duramax Gorilla Girdle Kit (LML)The thick Gorilla Girdle is the strongest girdle on the market. It utilizes the XXL ARP 14mm main studs. This 14mm girdle only fits the LML Engines from 2011 2017. Core charge on the upper oil pan 250. 00 Core charge is added to part price. We will credit the core charge back when we receive the old upper oil pan.