What is included in a complete brake job?
A complete brake job should restore the vehicle's brake system and
braking performance to good-as-new condition. Anything less would be
an incomplete brake job.
Brake components that should be replaced will obviously depend upon
the age, mileage and wear. There is no pat answer as to which items
need replacing and which ones don't. It's a judgment call.
A complete brake job should begin with a thorough inspection of the
entire brake system; lining condition, rotors and drums, calipers
and wheel cylinders, brake hardware, hoses, lines, and master
cylinder.
Any hoses that are found to be age cracked, chaffed, swollen, or
leaking must be replaced. Make sure the replacement hose has the
same type of end fittings (double-flared or ISO) as the original.
Don't intermix fitting types.
Steel lines that are leaking, kinked, badly corroded, or damaged
must also be replaced. For steel brake lines, use only approved
steel tubing with double-flared or ISO flare ends.
A leaking caliper or wheel cylinder needs to be rebuilt or replaced.
The same applies to a caliper that is frozen (look for uneven pad
wear), damaged or badly corroded.
Leaks at the master cylinder or a brake pedal that gradually sinks
to the floor tells you that the master cylinder needs replacing.
The rotors and drums need to be inspected for wear, heat cracks,
warpage, or other damage. Unless they are in perfect condition, they
should always be resurfaced before new linings are installed. If
worn too thin, replace them.
Rust, heat, and age have a detrimental effect on many hardware
components. It's a good idea to replace some of these parts when the
brakes are relined. On disc brakes, new mounting pins and bushings
are recommended for floating-style calipers. High temperature
synthetic or silicone brake grease (never ordinary chassis grease)
should be used to lubricate caliper pins and caliper contact points.
On drum brakes. shoe retaining clips and return springs should be
replaced. Self-adjusters should be replaced if they are corroded or
frozen. Use brake grease to lubricate self-adjusters and raised
points on brake backing plates where shoes make contact.
Wheel bearings should be part of a complete brake job on most
rear-wheel drive vehicles and some front-wheel drive cars. Unless
bearings are sealed, they need to be cleaned, inspected, repacked
with wheel bearing grease (new grease seals are a must), and
properly adjusted.
As a rule, tapered roller bearings are not preloaded. Finger tight
is usually recommended. Ball wheel bearings usually require
preloading.
As a final step, old brake fluid should always be replaced with
fresh fluid.
|
