Cat 416/420/430 etc brakes are known to be fast wearing and exceptionally dirty. There is no filter on the oil in the compartment and there is only about five gallons total. Thus no clean oil and no cooling.
In situations where brakes are used maybe more than normal or in roading long distances, the oil gets very hot and breaks down, thus no lubricity. The discs and plates get exceptionally hot and expand. That creates more friction. The result is poor longevity in the brakes, and the differential as well, as it's all shared hot and dirty oil in the compartment. I have seen these brakes fail in as little as two hundred hundred operating hours. The best I ever got out of them, rebuilt with the different lining material, was about 3700 hours.
One of the things you can do, is change the diff/brake compartment oil every 250 hours when you also change the engine oil. You can also instruct your operators to stay off the brakes as much as possible, and avoid long distance roading.
To repair, you can purchase replacement parts from New Holland, for some of their loader/backhoes share the same differential and brake assemblies. I have found their parts in the past to be a little cheaper than those from Cat.
Of course, if you have failure before your warranty is up, by all means head back to the Cat house and tell them to come out and fix it.
You can also purchase aftermarket brake discs from a firm that also sells the same type of lining for clutches. I believe they are out of Cleveland, but when their brake lining wears, as it will of course, it does not produce the type of material that wears out everything else in the compartment. Thus the brakes housings and pistons generally come out in reusable condition, also the steel plates and all the differential parts.
I managed a fleet of these machines in California, and had enough of them that I kept a rebuilt spare axle handy, which we rebuilt in our shop. I had a field man that could change out axle assemblies in about 30-40 minutes, vs several hours or days to remove, throughly clean, rebuild and reinstall them.
I might mention here that when rebuilding these components after they have basically been destroyed by wear, that the entire assembly has to come off the machine and be stripped down to nothing. All new bearings and seals must be installed and usually the entire brake assemblies and the differential assembly. You can not reuse old brakes plates with new discs or vice versa. That way you still have excessive wear, which causes a sloppy first brake application untill all the slack is taken out.
I have seen these brakes rebuilt with old plates and new discs, with one additional plate installed to take the assembly back within dimensions. But I don't advise this unless you are, or have a very competent mechanic who can measure accurately. Even then I don't believe I'd sanction it. But a poor boy outfit might want to.
Just before I got out of the industry, I'd heard that Cat was using a new brake material that supposedly did not wear out every thing else. I don't know for sure if that is still available or even if it ever was.
Good Luck!
