FRAME AS-REAR 3260879 - Caterpillar

Illustration 1 g00478200
Typical components of the Service Brakes (A) Thickness of a disc. (1) Piston. (2) Disc. (3) Plate.
The thickness (A) of a new disc (2) is 7.10 0.13 mm (0.280 0.005 inch). The minimum thickness (A) of a worn disc (2) should not exceed 5.64 mm (0.222 inch). Service the brake before disc (2) reaches the minimum thickness (A). Note: Check each service brake disc in each service brake.
Illustration 2 g00478267
Measuring the Depth of the Oil Grooves on the Service Brake DiscNote: Groove depth is the most critical dimension. The oil flow will be inadequate to the service brakes. If the depth of the grooves on the service brake discs are too shallow, oil flow to the service brakes will be inadequate.
Check the groove depth on both sides of the service brake disc. Use a wire gauge for this procedure.
The depth of the oil grooves must be greater than 0.32 mm (0.013 inch).
Table 1
Disc Thickness Wear Chart    
Estimated Percentage of Remaining Brake Disc Life     Remaining Thickness of Disc     Oil Groove Depth (1)    
100    
7.10 mm (0.280 inch)    
1.05 mm (0.041 inch)    
80    
6.80 mm (0.268 inch)    
0.90 mm (0.035 inch)    
60    
6.52 mm (0.257 inch)    
0.76 mm (0.030 inch)    
40    
6.22 mm (0.245 inch)    
0.61 mm (0.024 inch)    
20    
5.94 mm (0.234 inch)    
0.47 mm (0.018 inch)    
0    
5.64 mm (0.222 inch)    
0.32 mm (0.013 inch)    
( 1 ) Groove depth is the most critical measurement.