Part No. TT - 2013 TT - 2014 TT - 2015 TT - 2016 TT - 2017 TT - 2018 | Ball Diameter 46.70 46.70 50.80 50.80 50.80 58.80 | Thread Diameter 1" UNC 3/4" UNC 3/4" UNC 1" UNC 1" UNC 1" UNC | Shank Length 76.20 79.50 79.50 79.50 54.00 76.20 | Gross Load Rating lbs. 2,000 2,000 3,500 5,000 12,000 6,000 |