168-8451 bearings are used in the final drive gearbox system of Caterpillar heavy machinery equipment：311C, 315C, 315D L, 318B, 318C, 318D L, 319C, 319D, 319D L, 319D LN, 320B, 320C, 320C FM, 320C L, 320D, 320D FM, 320D GC, 320D L, 320D LN, 320D LRR, 320D RR, 321B, 321C, 321D LCR, 322B, 322B LN, 323D
