The wheel cylinders in the federal supply system have inferior springs which lack end expanders. The rebuild kits from most have either coned end springs or crimped on expanders. These are superior because they force the rubber cups outward, assuring good seal. This prevents seepage of brake fluid on trucks with poppet breathers on the master cylinder.
When the ambient temperature drops, the pressure inside the brake system can drop when the vehicle isn't being used. This causes the cups to pull back and brake fluid can seep. If the boots retain this leaked fluid, braking performance will suffer with soft pedal and long travel.
With silicone brake fluid, most wheel cylinders clean up easily with seconds of brake hone use.
A dab of silicone sealant on the keyway cork does a great job keeping gear lube migration to a minimum. Also great for axle flange sealing.
On the rears, pulling the duals and hubs as one unit is a time saver, if you have a wheel dolly or engine hoist. I use my long 3/8" extension through the rim windows, hooking it with the chain on the engine hoist for a near perfect single point lift. Beats busting lugs and Budd nuts. But if you need to swap drums, you are out of luck.
