4
Component Removal, Installation and Adjustment
19
Meritor
Maintenance Manual 14R (Revised 12-18)
20. While maintaining the seven to eight-inch (178-203 mm)
distance between the axle seat and frame, tighten the nuts on
the control arm pivot bolts to 450-500 lb-ft (611-678 N
폷
m).
@
21. Install the lower shock absorber bolt, nut and height control
valve tab (if rear axle). Tighten the shock absorber nut to
225-275 lb-ft (305-375 N
폷
m).
@
22. Install and tighten the bottom air springs nuts to 30-35 lb-ft
(41-47 N
폷
m).
@
23. Reinstall the brake chambers and slack adjusters.
24. Reinstall the brake shoes.
25. Reinstall the drums, tires and wheel ends using new seals and
lubricant.
26. Lower the axle and vehicle. Replenish the trailer’s air supply.
27. Check the suspension ride height to confirm it is correct.
앫
If the suspension ride height is not correct, and an
adjustment is required:
Refer to the ride height
adjustment procedures in this section.
28. Check the alignment to confirm it is correct.
앫
If the alignment is not correct, and an adjustment is
required:
Refer to the alignment adjustment procedures in
this section.
29. Paint or undercoat the replaced axle.
Axle Alignment
Before You Align the Axle
1.
Park the trailer on a level surface.
2.
Adjust the trailer landing gear so that the height of the king pin
is the same as when the trailer is connected to the tractor.
3.
Release the parking brakes. Block the wheels of the axle that is
not being aligned to keep the locking pins tight against the
same side of the body rail holes, front or rear.
Front Axle
1.
Verify that the suspension is at the correct ride height. Refer to
the trailer manufacturer’s specifications. Figure 4.16.
2.
Measure from the king pin to each end of the first axle,
measurements A and B. To obtain the correct alignment, the
difference between measurements A and B must not exceed
1/8-inch (3.175 mm). Figure 4.21.
앫
If adjustment is required:
Proceed to Step 3.
앫
If adjustment is not required:
Proceed to Step 4.
Figure 4.21
3.
Loosen the bolt that connects the front axle upper control arm
to the frame bracket located on the same side of the
suspension as the adjustable lower control arms. You must
loosen this connection before you align the axle to prevent
premature bushing and component damage. Loosen the lower
control arm clamp bolts.
4.
Align the axle so that the difference between measurements A
and B does not exceed 1/8-inch (3.175 mm). Figure 4.21.
5.
Adjust the length of the adjustable lower control arm as
required.
6.
Check the axle alignment from the king pin.
앫
If adjustment is required:
Repeat Steps 3 and 4 until the
alignment is correct.
앫
If adjustment is not required:
Proceed to Steps 7 and 8.
7.
When the axle is aligned correctly, tighten the lower control
arm clamp bolts to 160-170 lb-ft (217-231 N
폷
m).
@
8.
Tighten the upper control arm pivot bolt to 450-500 lb-ft
(611-678 N
폷
m).
@
Rear Axle
1.
Check the dimension from the centerline of the front axle to the
centerline of the rear axle, measurements C and D.
2.
To obtain the correct alignment, the difference between
measurements C and D must not exceed 1/16-inch
(1.588 mm). Figure 4.21.
Figure 4.21
1003517b
A
B
C
D
1/8" (3.175 MM)
1/16" (1.588 MM)
KING PIN
