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General Application
1967-1972 F-100 Specific
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INSPECTION
Now if your going to flat out replace every
component, you can skip the inspection. But if you're like myself and you are doing your
own brake work to save a little money, the inspection is a must.
The worst part about doing brakes, in my
option, is the inspection. I say it's the worst part, because you have to remove the drums
and inspect the brakes. This phase is dirty, time consuming and in many cases you
have to put everything back together if you don't have another vehicle to run parts.
We began the inspection by pulling the drums
and inspecting the linings and brake surfaces. For the rear brakes, this is pretty
simple. Safely jack the vehicle and remove the rear wheel. For the front, the
inspection is a little more involved since the hubs need to be removed.
 Prior to removing
the drums you will need to adjust all the brakes down. This will allow the linings to
clear the drum for removal. This step takes a little time, but it's well worth the
effort. I have watched people pry the drums off the linings, destroying springs and
bending back plates rather than adjust the shoes down.
For the rear brakes you many need to check to
see if there is a retaining clip on one or more of the axle lugs. This clip was used
to hold the drum in place until the wheel could be bolted on while on the assembly line.
It no longer serves a purpose and can be discarded. On the older vehicles, these
clips have long since been removed. If not, use a small chisel to the cut the clip.
The clips are made of a light spring steel and cut easily.
The rear drum can be stubborn if there is any
rust build up around the axle hub. Wire brushing and penetrating oil makes short
work of this problem. You make need to tap the drum lightly with a soft or dead blow
hammer to aid in it's removal from the axle.
As mentioned earlier, the inspection of the
front brakes requires the removal of the hub from the spindle. This is done by
removing the dust cap, retaining pin, spindle nut and retainer. The hub then can be
removed. If your inspection is part of the teardown, replace the spindle nut prior
to removal of the hub. Once the spindle nut is in place, pull the hub in a quick motion,
sliding across the top of the spindle. This action will pull the rear bearing and
seal at the same time. Any brake job should include the repacking or replacement of
the front wheel bearings.
 This photo shows
what a typical worn brake set will look like. Notice the rear shoe lining, it's
almost gone. While worn down, it is not into the metal part of the shoe. These were
"bonded linings", which mean that the braking material is bonded to the shoes
with an adhesive. Another method of securing the linings to the shoes is a combination of
adhesive and riveting. Had these linings been riveted, we would have been into the rivets
long ago. Many hobbyist prefer the bonded lining due to their longer life. In heavy
duty applications such as trucks, riveted linings are recommended.
During your inspection you will notice a lot
of brake dust. This coating of dust does help serve as a marker for identifying
leaks. Any leaks around the wheel cylinder seals or spindle seals will show up well
on this coating. On a teardown, leak identification is not as important as it is
during bearing service or other maintenance that causes you to have the drums off.
In this photo you can see a little seeping of brake fluid around the front wheel cylinder
seal. Take note on the rear brakes of any leakage around the axle seals.
The brake job should always include the
rebuilding or replacement of the wheel cylinders. This is an often over looked part
of brake work. New linings greatly increase wheel cylinder pressures. This
increased pressure will cause a weak cylinder to fail. Kiting a wheel cylinder every
2 or 3 years is a small price to pay for safety and reliability.
 Now we turn our attention to the braking
surface. In this photo you can the inside braking surface. The highlighted section shows
rivet cuts from a previous set of linings and chatter marks. Most of the minor
imperfections can be "Turned" or machined out. The photo below is the opposite
side and is in worse condition. Rivet scoring this heavy cannot be cleaned up by
machining. Replacement of the drum is the only option in such cases. Drums MUST always be
replaced in pairs.
Cast into most drums, is a number that
denotes the maximum machining tolerance. A quick measurement shows this drum to be
well over the maximum turning tolerance. So, we add new drums to our list of required
parts. The rear drum surfaces looked good and had enough material to safely turn.
The front bearings were in good shape, but
looked as they had been over-heated a little. The seals were reusable, but with the need
for new drums and bearings we decided to go with new seals too. We looked over the
brake hardware (springs) and they looked fine, but since we did not know how old they
were, we added them to our list as well.
 Parts List
& Machine Work:
- (2) New Front Drums
- (4) Wheel Cylinder Rebuild Kits
- (1) Set of Front Brake Hardware
- (1) Set of Rear Brake Hardware
- (1) Set of Front Brake Shoes
- (1) Set of Rear Brake Shoes
- (2) Sets of Front Bearings with Races
- (2) Front Bearing Seals
- (2) New Dust Caps
- (2) Turn Rear Brake Drums and Balance.
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