In 2013, PACCAR introduced a new seat spec for their new Kenworth (T800, T700, T680) & Peterbilt (587, 579) truck models which uses a unique bolt pattern (22" x 22" ). 

Many seat manufacturers are developing retro fit kits so that the seat can be swapped out to use a standard aftermarket seat.

Kits should include two tether straps, a cable and various hardware.  A template is provided to show where to cut through the floor mat to reach mounting holes for the seat that already exist in the cab floor.

For Installation questions, please contact the aftermarket seat manufacturer.