Western Star 47X 2020, Maintenance Manual

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41–00 Safety Precautions
Safety Precautions in this section apply to all
procedures within this group.
DANGER
When working on the vehicle, shut down the en-
gine, set the parking brake, and chock the tires.
Before working under the vehicle, always place
jack stands under the frame rails to ensure the
vehicle cannot drop. Failure to follow these steps
could result in serious personal injury or death.
41–01 Driveline Inspection
1. Park the vehicle on a level surface, apply the
parking brakes, and chock the tires.
CAUTION
Due to the extreme load occurring at high-speed
rotation, a loose or broken capscrew at any point
in the driveline will weaken the driveline connec-
tion, which could eventually result in serious ve-
hicle damage. Tighten bearing-cap capscrews or
yoke-strap capscrews to specified torque, being
careful to not overtighten.
2. Tighten the U-joint capscrews. See Table 1 for
torque specifications.
U-Joint Torque Specifications
Type Torque Figure
U-joints with bearing caps 43 lbf·ft (49 N·m) Fig. 1
Meritor RPL U-joints
(except RPL35)
125 lbf·ft (169 N·m) Fig. 2
Meritor RPL35 U-joints 150 lbf·ft (200 N·m) Fig. 4
U-joints with yoke straps 125 lbf·ft (169 N·m) Fig. 3
Table 1, U-Joint Torque Specifications
3. Check the driveline yokes or flanges for cracks,
and check end-yokes for looseness. See
Fig. 3 .
Replace cracked yokes and flanges.
If any end-yoke can be moved in or out on its
shaft, or can be rocked on its shaft, disconnect
the driveshaft and U-joint from the yoke, then
check the drive component’s shaft seal for leak-
age or other visible damage that may have been
caused by the loose yoke. Replace the seal if
needed, then tighten the yoke nut. Refer to
Group 41 of the Western Star 47X and 49X
Workshop Manual for torque specifications. If the
yoke is still loose after tightening the yoke nut,
replace the end-yoke and yoke nut.
Replace the prevailing torque locknut (end-yoke
nut) if it was removed for yoke replacement, seal
replacement, or any other reason.
4. Check U-joint assemblies for wear by moving the
driveshaft up and down, and from side to side. If
f410155a 10/06/2016
1
1 1
2
ME
R I TOR
1. Self-Locking
Capscrew 2. Adhesive Band
Fig. 1, Meritor U-Joint Fasteners for Bearing Caps
f410182 10/06/2016
Fig. 2, Meritor RPL Series U-Joint, Except RPL35
Driveline
41
47X and 49X Maintenance Manual, August 2020
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