Freightliner Coronado 132 / 122SD. Manual - part 24

Install the reservoir on the cover and tighten the
capscrews.

Fill the reservoir with 40 ounces (1183 mL) of
methyl alcohol, then install the filler cap.

42–05 Brake Inspection

Parking Brake Operational Check

IMPORTANT: This procedure should be per-
formed prior to lubrication of the brake compo-
nents.

CAUTION

Perform the following check in a clear safe area. If
the parking brakes fail to hold the vehicle, per-
sonal injury or property damage may result.

With the engine running, and air pressure at cut-
out pressure, set the parking brake.

Put the vehicle in the lowest gear and gently at-
tempt to move it forward. The vehicle should not
move. If the vehicle moves, the parking brakes
are not operating correctly and must be repaired
before the vehicle is returned to service. See
Group 42 of the vehicle Workshop Manual for
repair procedures.

Brake Component Inspection

Park the vehicle on a level surface, set the park-
ing brake, and chock the tires. Once the tires are
chocked, release the parking brake.

WARNING

Manually adjusting an automatic slack adjuster to
bring the pushrod stroke within legal limits is
likely masking a mechanical problem. Adjustment
is not repairing. Before adjusting an automatic
slack adjuster, troubleshoot the foundation brake
system and inspect it for worn or damaged com-
ponents. Improperly maintaining the vehicle brak-
ing system may lead to brake failure, resulting in
property damage, personal injury, or death.

With the engine off, and 100 psi (689 kPa) of air
tank pressure, have an assistant apply and hold
an 80 to 90 psi (550 to 620 kPa) brake applica-
tion.

Check to see if the colored over-stroke band on
each brake chamber pushrod is exposed.

If a band shows, the stroke is too long. Check
the foundation brake components for wear or
damage, and repair as needed. See Group 42 of
the vehicle Workshop Manual for inspection and
repair procedures.

Measure the applied chamber stroke.

See

Table 1

for the proper stroke for the type of

chamber being used. If the stroke is too short,
the brakes may drag or will not fully apply. Check
for improper operation or adjustment of the auto-
matic slack adjuster. See Group 42 of the ve-
hicle Workshop Manual.

Brakes

42/6

Brake Chamber Stroke Specifications

Chamber

Max Applied Stroke: inch (mm)

Manufacturer

Type

Size

†

Gunite

Standard Stroke

1-3/8 (35)

1-3/4 (44)

2 (51)

‡

2-1/4 (57)

Long Stroke

2 (51)

24 (2-1/2 inch rated

stroke)

24 (3 inch rated

stroke)

2-1/2 (64)

Haldex

Standard Stroke

1-3/8 (35)

1-3/4 (44)

2-1/2-Inch Extended Stroke

2 (51)

3-Inch Extended Stroke

2-1/2 (64)

Standard Stroke

2 (51)

Long Stroke

2-1/2 (64)

Meritor

Standard Stroke

Less than 1-1/2 (38)

Less than 1-3/4 (44)

Less than 1-7/8 (48)

Long Stroke

Less than 2 (51)

Standard Stroke

Brakes

42/7

Brake Chamber Stroke Specifications

Chamber

Max Applied Stroke: inch (mm)

Manufacturer

Type

Size

†

Dana Spicer

Long Stroke

16L

2 (51)

20L

24L

24LS

2-1/2 (64)

30LS

Long stroke design is indicated by a tag, or embossing, on the brake chamber.

†

Specifications are relative to a brake application with 80 to 90 psi (550 to 620 kPa) air pressure in the brake chambers.

‡

If type 36 chamber is used, slack length should be less than 6 inches.

Table 1, Brake Chamber Stroke Specifications

Start the engine and build air pressure to at least
100 psi (689 kPa). Shut down the engine.

Check all of the foundation brake components for
damage, wear, and loose or missing parts. Re-
pair as needed. See Group 42 of the vehicle
Workshop Manual for repair procedures.

42–06 Meritor Camshaft

Bracket Lubrication

IMPORTANT: Perform a brake inspection before
lubricating the camshaft bracket.

NOTE: If equipped with an extended-
maintenance Q Plus

™

brake system, the cam-

shaft bracket will not have a grease fitting.
These camshafts use a special NLGI Grade
synthetic polyurea grease and do not require
lubrication for 3 years or 500,000 miles (800
000 km), whichever comes first. The extended-
maintenance camshaft bushings are lubricated
during the brake reline service interval. For ser-
vice and lubrication instructions, see Group 42
of the vehicle Workshop Manual.

For camshaft brackets with grease fittings, use an
NLGI Grade 1 or Grade 2 multipurpose chassis
grease. Lubricate the camshaft bushings through the
grease fitting on the camshaft bracket or the spider
until new grease flows from the inboard seal. See

Fig. 5

WARNING

If grease leaks out under the camhead, the cam-
shaft bracket grease seal is worn or damaged. See
Group 42 in the vehicle workshop manual for
grease seal replacement instructions. If this seal
is not replaced, the brake linings could become
contaminated with grease. The stopping distance
of the vehicle will be increased, which could result
in personal injury or property damage.

f420011a

05/28/93

A. Grease Exit
1.

Brake Chamber

Slack Adjuster

Non-Pressure-Relief
Grease Fitting

Fig. 5, Camshaft Bracket Lubrication

Brakes

42/8

42–07 Meritor Slack Adjuster

Lubrication

IMPORTANT: Perform a brake inspection follow-
ing the instructions in this group before lubricat-
ing the slack adjusters.

WARNING

Failure to lubricate slack adjusters could lead to
dragging brakes or a brake failure, resulting in
property damage, personal injury, or death.

NOTE: If equipped with an extended-
maintenance Q Plus

™

brake system, the slack

adjuster will not have a grease fitting. These
slack adjusters use a special NLGI Grade syn-
thetic polyurea grease and do not require lubri-
cation for 3 years or 500,000 miles (800 000
km), whichever comes first. The extended-
maintenance slack adjusters are lubricated dur-
ing the brake reline service interval. For service
and lubrication instructions, see Group 42 of
the vehicle Workshop Manual.

For slack adjusters with grease fittings and for oper-
ating temperatures above –40°F (–40°C), use an
NLGI Grade 1 clay-base grease, or an NLGI Grade 1
or 2 lithium-base grease.

For slack adjusters with grease fittings and for oper-
ating temperatures below –40°F (–40°C) and above
–65°F (–54°C), use an NLGI Grade 2 synthetic oil,
clay-base grease.

Lubricate the slack adjuster at the grease fitting until
grease is forced past the pressure-relief capscrew or
past the gear splines around the inboard snap ring.
See

Fig. 6

42–08 Dana Spicer Camshaft

Bracket Lubrication

IMPORTANT: Perform a brake inspection before
lubricating the camshaft bracket.

Pump grease into the camshaft bracket until it ap-
pears at the slack adjuster end of the bracket. See

Fig. 5

Use an NLGI Grade 1 or Grade 2 multipurpose chas-
sis grease. If grease leaks out under the camhead,
the camshaft bracket grease seal is worn or dam-
aged; replace it. See Group 42 of the 122SD and
Coronado Workshop Manual for grease seal replace-
ment instructions.

42–09 Dana Spicer, Haldex,

and Gunite Slack
Adjuster Lubrication

IMPORTANT: Perform a brake inspection before
lubricating the camshaft bracket.

Automatic slack adjusters that have a grease fitting
must be lubricated periodically to ensure proper
brake operation.

WARNING

Failure to lubricate slack adjusters could lead to
dragging brakes or a brake failure, resulting in
property damage, personal injury, or death.

f420012a

10/20/93

Brake Chamber

Clevis

Actuator Rod

Boot

Pressure-Relief Capscrew, Gasket, Pawl Spring,
and Pawl

Manual Adjusting Nut

Grease Fitting (or plug)

Fig. 6, Meritor Automatic Slack Adjuster

Brakes

42/9

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