Dodge Sprinter. Manual - part 19

check suspension components. Jounce front and rear
of vehicle and listen for noise that might be caused
by loose, worn or damaged suspension or steering
components.

(3) Inspect brake fluid level and condition. Note

that the brake reservoir fluid level will decrease in
proportion to normal lining wear. Also note that
brake fluid tends to darken over time. This is
normal and should not be mistaken for contam-
ination.

(a) If fluid level is abnormally low, look for evi-

dence of leaks at calipers, wheel cylinders, brake
lines, and master cylinder.

(b) If fluid appears contaminated, drain out a

sample to examine. System will have to be flushed
if fluid is separated into layers, or contains a sub-
stance other than brake fluid. The system seals
and cups will also have to be replaced after flush-
ing. Use clean brake fluid to flush the system.
(4) Check parking brake operation. Verify free

movement and full release of cables and pedal. Also
note if vehicle was being operated with parking
brake partially applied.

(5) Check brake pedal operation. Verify that pedal

does not bind and has adequate free play. If pedal
lacks free play, check pedal and power booster for
being loose or for bind condition. Do not road test
until condition is corrected.

(6) Check booster vacuum check valve and hose.
(7) If components checked appear OK, road test

the vehicle.

ROAD TESTING

(1) If complaint involved low brake pedal, pump

pedal and note if it comes back up to normal height.

(2) Check brake pedal response with transmission

in Neutral and engine running. Pedal should remain
firm under constant foot pressure.

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BRAKES - BASE

(3) During road test, make normal and firm brake

stops in 25-40 mph range. Note faulty brake opera-
tion such as low pedal, hard pedal, fade, pedal pulsa-
tion, pull, grab, drag, noise, etc.

(4) Attempt to stop the vehicle with the parking

brake only and note grab, drag, noise, etc.

PEDAL FALLS AWAY

A brake pedal that falls away under steady foot

pressure is generally the result of a system leak. The
leak point could be at a brake line, fitting, hose, or
caliper/wheel cylinder. If leakage is severe, fluid will
be evident at or around the leaking component.

Internal leakage (seal by-pass) in the master cylin-

der caused by worn or damaged piston cups, may
also be the problem cause.

An internal leak in the ABS or RWAL system may

also be the problem with no physical evidence.

LOW PEDAL

If a low pedal is experienced, pump the pedal sev-

eral times. If the pedal comes back up worn linings,
rotors, drums, or rear brakes out of adjustment are
the most likely causes. The proper course of action is
to inspect and replace all worn component and make
the proper adjustments.

SPONGY PEDAL

A spongy pedal is most often caused by air in the

system. However, thin brake drums or substandard
brake lines and hoses can also cause a spongy pedal.
The proper course of action is to bleed the system,
and replace thin drums and substandard quality
brake hoses if suspected.

HARD PEDAL OR HIGH PEDAL EFFORT

A hard pedal or high pedal effort may be due to

lining that is water soaked, contaminated, glazed, or
badly worn. The power booster or check valve could
also be faulty.

PEDAL PULSATION

Pedal pulsation is caused by components that are

loose, or beyond tolerance limits.

The primary cause of pulsation are disc brake

rotors with excessive lateral runout or thickness vari-
ation, or out of round brake drums. Other causes are
loose wheel bearings or calipers and worn, damaged
tires.

NOTE: Some pedal pulsation may be felt during
ABS activation.

BRAKE DRAG

Brake drag occurs when the lining is in constant

contact with the rotor or drum. Drag can occur at one
wheel, all wheels, fronts only, or rears only.

Drag is a product of incomplete brake shoe release.

Drag can be minor or severe enough to overheat the
linings, rotors and drums.

Minor drag will usually cause slight surface char-

ring of the lining. It can also generate hard spots in
rotors and drums from the overheat-cool down pro-
cess. In most cases, the rotors, drums, wheels and
tires are quite warm to the touch after the vehicle is
stopped.

Severe drag can char the brake lining all the way

through. It can also distort and score rotors and
drums to the point of replacement. The wheels, tires
and brake components will be extremely hot. In
severe cases, the lining may generate smoke as it
chars from overheating.

Common causes of brake drag are:
• Seized or improperly adjusted parking brake

cables.

• Loose/worn wheel bearing.

• Seized caliper or wheel cylinder piston.

• Caliper binding on corroded bushings or rusted

slide surfaces.

• Loose caliper mounting.

• Drum brake shoes binding on worn/damaged

support plates.

• Mis-assembled components.

• Long booster output rod.
If brake drag occurs at all wheels, the problem

may be related to a blocked master cylinder return
port, or faulty power booster (binds-does not release).

BRAKE FADE

Brake fade is usually a product of overheating

caused by brake drag. However, brake overheating
and resulting fade can also be caused by riding the
brake pedal, making repeated high deceleration stops
in a short time span, or constant braking on steep
mountain roads. Refer to the Brake Drag information
in this section for causes.

BRAKE PULL

Front brake pull condition could result from:
• Contaminated lining in one caliper

• Seized caliper piston

• Binding caliper

• Loose caliper

• Rusty caliper slide surfaces

• Improper brake pads

• Damaged rotor
A worn, damaged wheel bearing or suspension

component are further causes of pull. A damaged
front tire (bruised, ply separation) can also cause
pull.

A common and frequently misdiagnosed pull condi-

tion is where direction of pull changes after a few
stops. The cause is a combination of brake drag fol-
lowed by fade at one of the brake units.

BRAKES - BASE

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