B
102
Repair and Service Manual
MECHANICAL BRAKES
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
699327
Fig. 18 Check Clevis Pins
11. Tighten the jam nut at the spherical nut to the torque
values below.
Parking Brake Latching Force
Tool List
Qty.
Bathroom Scale ........................................................... 1
The parking brake latching force can be checked as ver-
ification after setting brake pedal free travel.
1.
Place a ‘bathroom’ scale on the service and parking
brake pedals.
2.
Using both feet, press the scale down against the
parking brake pedal until it latches.
3.
The parking brake should latch between 60 and 70
lbs. (27 - 32 kg) indicated on the scale (Ref Fig. 19).
Fig. 19 Checking Parking Brake Latching Pressure
4.
Perform the Periodic Brake Performance Test.
Return the vehicle to service if the brake perfor-
mance is satisfactory (See Periodic Brake Perfor-
mance Test (PBPT) on page 97).
Brake Drum Removal and Installation
Tool List
Qty.
Socket, 28 mm.............................................................1
Pliers, Needle Nose .....................................................1
Screwdriver, Straight Blade .........................................1
Floor Jack ....................................................................1
Jack Stands .................................................................2
Torque Wrench, ft. lbs. .................................................1
Anti-Seize Compound..............................................A/N
1.
Raise and support the rear of the vehicle (See LIFT-
ING THE VEHICLE on page 9).
2.
Remove the cotter pin (2).
3.
Remove the castellated nut (3) and washer (4).
NOTICE: Do not apply the brake when removing the
nut. The shoes may not fully retract preventing
removal of the brake drum.
4.
Slide the brake drum (1) from the axle shaft (5). If
required, tap the drum with a plastic faced hammer
to loosen it from the axle shaft or use a drum puller
(P/N 15947-G1) (Ref Fig. 20).
Fig. 20 Brake Assembly
Use caution when raising the
adjuster arm. Too much force will
damage the adjuster and require
that both wheel brake assemblies be
replaced.
5.
If the drum does not slide from the brake assembly,
the brake shoes must be retracted.
6.
Rotate the hub so that the hole in the drum is in the
six o’clock position which is directly over the brake
mechanism.
7.
Use a small straight blade screwdriver to raise the
adjuster arm
just above
the star wheel.
Item
Torque Specification
Jam Nut
10 - 11 in. lbs. (14 - 15 Nm)
Clevis Pin Loose?
If required, adjust the spherical
nut to achieve correct parking brake
latching pressure of 60 - 70 lbs.
(27 - 32 kg).
Loosen Jam Nut
Use a 'bathroom' scale
to confirm the latching force
required to engage and latch
the parking brake.
60 65 70
2
1
3
4
6
Front of Vehicle
5
PRELIMINARY
