GEAR 8F1483 - Caterpillar

973 LoadersDescription of Change: Hardened washers are now used on retainer bolts in the bottom guard groups for 963 and 973 Loaders. The new hard washers will hold the bolt torque of 135 15 N m (100 11 lb ft) better without distortion. Formerly, it was possible for distortion of the washers to permit the bolts to loosen.Adaptable As: The new 6V6563 Hard Washers are a direct replacement for the former 9P8856 Washers in this application. Twenty-six washers are used per machine. The new washers can be installed on all earlier machines equipped with guards that use 7N2597 Spacers (963 Loaders) or 4S9642 Bosses (973 Loaders) through the bolt holes in the guard plates. An explanation of this guard design on 963 Loaders is given in an article "Improved Mounting Of Bottom Guard Group Prevents Loose Bolts" on Page 6 of the March 1, 1982 Service Magazine.