Ford F-650 Owner's Manual page 186

Maintenance and Specifications
Air dryer: Climactic conditions affect performance of desiccant or
after-cooler type air dryers. Maintenance schedules must be established
for each specific operation.
The use of an air dryer on a vehicle does not eliminate the need to
periodically drain the air reservoirs.
Desiccant air dryer: Inspect for moisture in the air system by opening
reservoirs, draincocks or valves and checking for presence of water. The
presence of small amounts of water due to condensation is normal and
should not be considered as an indication that the dryer is not
functioning properly.
The desiccant cartridge should be replaced or rebuilt when it has been
determined that the desiccant is contaminated and does not have
adequate water absorption capacity. The desiccant change interval may
vary; it is generally recommended that the desiccant be replaced every
12 months (yearly). If experience has shown that extended or shortened
life has resulted for a particular installation, then the yearly interval can
be increased or decreased accordingly.
Hydraulic brakes
Inspection and adjustment: Establish a regular schedule for periodic
cleaning, lubrication and adjustment inspection based on vehicle use.
Exact maintenance intervals are difficult to predetermine since vehicles
are used in a wide variety of applications and conditions; if you are
uncertain of the proper schedule for your vehicle, contact your dealer.
Inspect the brake lining every maintenance interval. Establish inspection
intervals that provide for lining replacement before damage to the disc
occurs. Excessive lining wear may expose the backing plate to the disc
causing scoring of the disc faces. This inspection should be performed by
a qualified technician and must be in accordance with instructions
provided by the service manual. Hydraulic brake systems are
power-assisted. Braking capabilities are greatly reduced without engine
assist.
Fluid level: Fluid level should be at the bottom edge of the ring on each
reservoir fill port. Do not fill the master cylinder to the top of the
reservoir. If fluid level requires attention to maintain a proper master
cylinder level, this is an indication of either severe operation (pad wear)
or fluid leakage. A more frequent and thorough brake inspection is
required.
186
2012 F-650/750 (f67)
Supplement, 2nd Printing
USA (fus)