The General Motors 9.5-inch axle is available as a 14-bolt differential. The cover plate of the differential has 14 bolts securing the plate to the housing. The 9.5-inch axle was installed exclusively in the light duty, 3/4-ton pickups produced between 1986 and 1993. Primarily installed in the heavy duty, or HD, pickup trucks and SUVs, the 14-bolt, 9.5-inch axle was installed on millions of GM vehicles during seven years of production.
The 9.5-inch axle is rated to support up to 5,000 pound-feet of torque. Installed as a heavy-duty option on 3/4-ton pickups, this axle is commonly installed on the lighter 1/2-ton pickups because of the perfect fit -- 67 inches -- between wheels on many models.
The 14-bolt differential cover bolts should be torqued to a maximum of 20 pound-feet during installation. Apply even tension during the tightening process by tightening opposite side bolts rather than tightening in a clockwise or counterclockwise tightening sequence. Tighten each side of the cover plate, then the top and bottom and then individual bolts; tighten the opposing bolt before moving to the next sequence.
When installing the ring gear in the 9.5-inch axle, tighten the ring gear bolt securely to the case with 105 pound-feet of torque.
When installing the side bearing caps, tighten them to 60 pound-feet of torque.
Torque is measured in pound-feet, which is a measurement of the rotational pressure required to tighten or turn an object. Measured 1 foot away from the pivot point -- bolt, screw or otherwise -- the measurement defines how many pounds of pressure is required to turn the object. For example, 50 pound-feet of torque requires 50 pounds of pressure to turn if using a lever from exactly 1 foot away.
