Manitowoc Grove RT770E, Service Maintenance Manual

Page: 278 / 357

UNDERCARRIAGE RT770E
8-2 Published 11/26/2014, Control # 447-05
reduction, through the revolving planet gears, and into the
planetary spider which drives the wheel hub.
As an option, the front axle and rear axle may be provided
with a differential lock. When in the locked mode, the axle
shafts and the differential are locked together and there is no
differential action between the wheels.
Maintenance
NOTE: The axles do not have to be removed from the
crane to remove the planetary wheel ends or the
drive units.
Removal
1. Using the outriggers, raise the wheels off the ground.
2. Install blocking under the frame at the outboard ends of
the four outrigger boxes.
3. Disconnect and remove the drive line from the
applicable axle. Do not disassemble the drive lines.
Refer to
Drive Shafts , page 7-24.
4. Tag, disconnect, and cap the hydraulic brake line at
each wheel.
5. Tag, disconnect, and cap the hydraulic lines to the steer
cylinders.
6. On the front axle only, tag and disconnect the hydraulic
line from the park brake actuator.
7. On the left side of the rear axle only, tag and disconnect
the electrical wires from the rear wheels not centered
switch.
NOTE: Each tire and wheel installation weighs
approximately 1360.7 kg (3000 lb).
8. Remove the wheels from the axle.
NOTE: Each axle weighs approximately 1400 kg (3086 lb).
9. Position jacks, which are capable of handling the weight
of the axle, under the axle for support.
10. Remove the eight nuts, washers, bushings and bolts
securing the axle to the frame/cradle.
11. Lower the axle to the ground and move it to a clean
working area.
12. If a new axle is to be installed, remove the following from
the old axle and install them on the new one.
a. The steer cylinders.
b. The rear wheels not centered switch actuator
bracket (rear axle only).
c. The parking brake actuator (front axle only). Refer
to
Brake System , page 8-13 in this section.
Cleaning
Completely assembled axles may be steam cleaned on the
outside only, to facilitate initial removal and disassembly,
providing all openings are closed. Breathers, vented shift
units, and all other openings should be tightly covered or
closed to prevent the possibility of water entering the
assembly.
Installation
1. If a new axle is to be installed, remove the following from
the old axle and install them on the new one.
a. The steer cylinders.
b. The rear wheels not centered switch actuator
bracket (rear axle only).
c. The parking brake actuator (front axle only). Refer
to
Brake System , page 8-13 in this section.
2. Position the axle under the crane on jacks which are
capable of handling the weight of the axle.
3. Raise the axle into place and secure with the eight
attaching bolts, washers, bushings and nuts. Torque the
bolts to 759 Nm to 822 Nm (560 lb-ft to 606 lb-ft).
4. Install the wheels onto the axle. Refer to Wheels And
Tires , page 8-4 in this section.
5. Connect the hydraulic lines to the steer cylinder as
tagged during removal.
6. Connect the hydraulic brake line to each wheel as
marked during removal.
7. On the front axle only, connect the hydraulic line to the
parking brake actuator.
8. On the left side of the rear axle only, connect the
electrical wires to the rear wheels not centered switch.
Adjust the switch as outlined under,
Rear Steer Indicator
Adjustment Procedure , page 8-3.
9. Connect the drive line to the applicable axle. Refer to
Drive Shafts , page 7-24.
10. Refer to Brake System , page 8-13 and bleed the
hydraulic brake system.
11. Remove the blocking under the frame and retract the
outriggers to lower the wheels to the ground.
CAUTION
Do not disassemble drive lines when removing them from
the crane. Dirt can enter the spline and cannot be purged.
In addition, the drive lines are assembled in a specific
orientation when manufactured and can easily be
incorrectly reassembled.