Great Compatibility — Fit for Paccar PX-6, 1989-2016 Cummins 4BT 3.9L,ISC 8.3L, B Series 5.9L, ISB, ISL 5.9L 6.7L, QSB 5.9L 6.7L. Work on seals and wear sleeves such as 3937111, 3904353, 3802820, 3934486, 5259499, 3926126, 3925529 and 4890833.