Ford 2013 F-650 Owner's Manual page 210

Air Brakes
WARNING: Do not manually adjust the automatic slack adjusters
to correct excessive push rod stroke as it may result in reduced
brake effectiveness and a vehicle crash. Excessive push rod stroke
indicates that a problem exists with the automatic adjuster, with the
installation of the adjuster, or with foundation brake components that
manual adjustment does not remedy. Seek service from a qualified
facility for excessive push rod stroke.
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.
Regular inspections should include:
• periodic checking (every service interval) of push rod travel or brake
adjustment. This is essential for effective braking. Brake chamber
push rods on original equipment chambers now incorporate an orange
paint marker near the base of the push rod as a stroke indicator to
aid in adjustment checks. If the push rod is clean and the brakes are
out of adjustment, the orange marker can be seen protruding from
the chamber when the brakes are applied.
• checking the brake lining (every service interval). When brake lining
or blocks are worn to within 1/16th inch (1.6 millimeters) of rivets,
replace the brake linings. This inspection or adjustment should only
be performed by a qualified technician and must be in accordance
with instructions provided by the service manual.
Do not back off or disconnect the front brakes so that they are less
effective, letting the rear brakes do all the stopping of the vehicle. Do
not overlook the brakes on the trailer either. Brake condition on the
trailer is just as important as the tractor. Proper brake balance on trucks
and tractor-trailers is essential for effective braking.
Once a year, the entire brake system must be inspected:
• Rubber components for deterioration. These components should be
inspected by a qualified technician and replaced as necessary.
Replacement intervals vary according to the severity and length of
vehicle service.
• Condition of brake drums, brake chambers and slack adjusters.
• System for air leaks.
• Hose or pipes for rust, damage and deterioration.
• Operation of service and parking brakes.
2013 F-650/750 (f67)
Owners Guide gf, 2nd Printing, March 2013
USA (fus)
Maintenance 209