Axle end thrust is taken by the cross shaft. This unit utilized a spring-preloaded cone friction arrangement for the locking action. The Dana Power-Lock can be recognized by its bolt-together assembly, bolts around the side opposite the ring gear, and multiple openings exposing the cross shafts.ġ969-1974 used the Borg Warner Spin Resistant (# 2881343). The axle bearings are: 25590 Timken cone, and 25520 cup, Chrysler numbers 1790503). This Sure Grip appeared in the 741 and 742 assemblies. In this assembly, axle drive shaft end thrust is taken by the thrust block assembly (replacement # 2881313). The Power-Lock can be rebuilt using kit # 2070845 ( Mopar Performance PT # P4529484 ).
This unit utilized clutches for the differential locking action. "Sure Grip" is the Chrysler name for a limited slip differential. Remove the carrier.may require prying, fluid will drain when carrier gasket seal is broken.Īny 8-3/4" center section may be interchanged for another as an entire assembly. Remove the 10 nuts on the housing studs around the carrier perimeter. Remove the axle shafts, 5 bolts on the backing plate flange on post 64 units, use puller for pressed-in pre-65 units. Chrysler Cars made pre-1965 units have a pressed-on brake hub. To remove the center section, remove the wheels, brake drums, and drive shaft. The axle tubes are part of the overall housing. The rear of the housing is smooth, the back is welded onto the main housing. It is retained by 10 nuts on studs in the housing. The 8-3/4" center section is removed from the front of the housing. Ratio can be determined by the number of teeth on the ring gear divided by the number of teeth on the pinion gear or by counting the ratio of the number of turns of the pinion relative to one turn of the axle shaft. On OEM gear sets, the ratio is usually stamped on the edge of the ring gear. If Sure Grip equipped, an additional Sure Grip lube tag was sometimes affixed later years sometimes had the filler plug painted orange. After 1965, a tag was affixed under one of the carrier mounting nuts to identify the ratio. Through 1965, the factory ratio was stamped on the identification boss, followed by an S if Additionally, the 741 commonly has a large X cast on the left side, the 742 may have a large 2 cast on the left side, and the 489 has a large 9 cast on the left side. Differential bearing setting (backlash) is set with threaded adjusters.Īll 8-3/4" carrier assemblies can be identified externally by the casting numbers. Pinion depth is set with shims, preload is set with a crush sleeve. This assembly was typically used in high weight/medium horsepower through high weight/high horsepower applications. By 1973, the 489 was the only unit available in passenger car applications. This assembly was introduced in 1969 and gradually replace the 1-3/4" unit through 1970 The 1-3/4" pinion also appeared in some 489 carriers during this period. backlash ) is set with threaded adjusters.ġ-7/8" tapered stem pinion. Pinion depth and bearing preload is set with shims. This assembly was typically used in high weight/medium horsepower applications through high weight/high horsepower applications. 1970 Plymouth and Dodge b Bodies were the last models to use the 1-3/4" which appeared in a 2881489 case. This assembly was replaced by a 1-7/8" pinion starting in the 1969 model year. backlash ) is set with threaded adjusters.ġ-3/4" large stem pinion. This assembly was typically used in low weight/low horsepower (Small Block as an example) applications through low weight/medium horsepower and high weight / low horsepower applications.
These numbers are found on the left side of the carrier assembly. The choice of axle pinion assembly was determined based on the application.ġ-3/8" small stem pinion (741) Carrier casting numbers: 1820657 (1957-1964), 2070741 (1964-1972). The types are differentiated by the pinion stem diameter.1-3/8", 1-3/4", 1-7/8". The 8-3/4" axle was available in three basic types. The 8-3/4" axle was the primary axle assembly used in most car lines through 1972.
There are three basic types available distinguished by their drive pinion stem diameter. The axle has an 8-3/4" diameter ring gear. It is a banjo-type, the differential is contained in a removable carrier assembly. The Chrysler 8-3/4" rear axle assembly was introduced in 1957. Thought this would help some people out with 8 3/4 axles