Document 5borQEde309adB0rE1MwDDpze

a ERVICE DECEMBER 22, 1977 T BULLETI %0. Q93 under brakes PLAINTIFF'S EXHIBIT FOR BRANCHES, DISTRIBUTORS AND CUSTOMERS. / ^ CHASSIS AFFECTED ALLENTOWNgf HAYWARD0 OAKVILLE CAM BRAKE ASSEMBLIES (All Highway Models With SW56C, 57C Series Bogies and FAW5361C, 5371C Series Front Axles) PURPOSE To inform the field of changes in cam brake usage and to describe means of identifying the various brake assemblies involved. RECOMMENDATION Advise service personnel of these changes in brake application to eliminate possible errors with respect to service procedure and replacement parts. INFORMATION Bogie Brakes - The SW56C (34, 000 lb.) and SW57C (38, 000 lb.) bogies will be built with either of two cam brake assemblies. The brake used will depend on vehicle model and application, not bogie model. This is in contrast to past prac tice whereby a particular bogie model would be equipped with one standard brake assembly. Brake assemblies that will be installed are Rockwell "P" series 16 1/2 x 7 and Eaton 16 1/2 x 7 cam brakes. The Rockwell brake is shown in Figure 1, the Eaton brake in Figure 2. Note from the illustrations that these assemblies can be identified by the number of anchor pins; two are used on the Rockwell brake and one is used on the Eaton brake. rtIN U D IN USA. 1. ANCHOR PINS (TWO) FIGURE 1 ROCKWELL BOGIE BRAKE ASSEMBLY 1. ANCHOR PIN (ONE) FIGURE 2 EATON BOGIE BRAKE ASSEMBLY CIRCULATIC Service Manager Shop Foreman Night Foreman Night Foreman Inspector Leadman Inspector Lea dm an Inspector Leadman Unit Over haul Room Service Operations, Allentown, Pa. U.S.A. ~ Mack Front Axle Brakes - Front axles FAW5361C and FAW5371C will be built with 15 x 4 cam brakes supplied by either Rockwell or Wagner. They will be used interchangea bly; actual usage depending on availability and production requirements. Subject ax les are used on F, R and U model six-wheel tractors. These brakes are illustrated in Figure 3 for Rockwell and Figure 4 for Wagner. The easiest method of identification is by shoe return spring arrangement. Rockwell as semblies utilize a single spring whereas Wagner assemblies have two springs con nected by a link. A second means of identification is by cam configuration. The Rockwell cam has a relatively flat surface opposite the cam face. The Wagner cam is similar but has more of a hook shape at the tip. Another identifying feature is brake chamber bracket construction. Rockwell brackets are fabricated, Wagner brackets are cast. 1. SHOE RETURN SI 2. CAM FIGURE 3 ROCKWELL "T" SERIES FRONT WHEEL CAM BRAKE ASSEMBLY FIGURE 4 WAGNER FRONT WHEEL CAM BRAKE ASSEMBLY