WHEEL 4559761 - Caterpillar

A change in the braking characteristics or a low pressure warning may be an indication of a failure in one of the brake circuits. Personal injury or death may occur if the machine is operated before repairs have been made or before all circuits have been checked. Always check the brakes after brake repairs have been made and before the machine is put back into use.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products.Dispose of all fluids according to local regulations and mandates.
Reference: For more information on preparing the machine for troubleshooting, refer to the Service Manual module Testing and Adjusting, "Machine Preparation for Troubleshooting". Brake service life can vary greatly because of the different applications and operator technique.Excessive heat can be generated if the service brakes are used as a retarder. Excessive heat can be generated if the service brakes are used as a device to maintain a slower ground speed. This type of operation should be avoided by using a lower transmission gear speed. Check the grooves on both sides of each disc in both the front and rear service brakes. The wear of the service brake disc may vary from one end of the machine to the other end, and from one side of the machine to the other side. The estimated wear for a given groove depth is shown in table 1.It is very important to change the friction discs as soon as possible once the groove depth has reached the maximum wear limit. As the depth of the grooves is reduced, the flow of the cooling oil is reduced. This causes heat to build up. The heat causes the rapid wear of the disc material. Eventually, the friction material will wear off the disc. This will cause metal to metal contact between the disc and plates. This problem is known as spalling.Spalling will destroy the very smooth surface finish of the plate. This will make replacement of these brake components necessary. If the failure has progressed to metal to metal contact, the complete axle must be thoroughly cleaned. This process of cleaning the axle must be done correctly, or the debris will continue to contaminate the oil. This will cause the material on the service brake disc to wear rapidly. This condition will cause premature failure of the service brakes.If excessive brake wear or premature brake wear is suspected, perform a scheduled oil sampling. This report could help establish a possible cause for failure of the service brakes.
Illustration 1 g01211854
Components to Check for Wear in the Service Brakes
(1) Plate
(2) Friction disc The thickness of a new friction disc (2) is 6.10 0.13 mm (.240 .005 inch).The recommended minimum thickness