GM Corp. 10-Bolt 8.5"- Ring & Pinion

Applications: 77-up Front axles K10, K20 & Blazer (F/S)rear axles 72-up passenger & 89-up K10, K20 & Blazer (F/S) Case Changes: Low 2.56 only and High 2.73 - 5.57

GGG885488 4.88 ratios

GGG885513 5.13 ratios

GGGM10-85-307 3.07 ratios

GGGM10-85-342 3.42 ratios

GGGM10-85-373 3.73 ratios

GGGM10-85-410 4.10 ratios

GGGM10-85-456 4.56 ratios