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To align a four (4) spring suspension there is one adjustable torque arm on each axle.
Release the clamps at each end of the adjusting screw. Align front axle with the king pin
and adjust each axle thereafter parallel to the front axle. Be sure to secure the clamps on
the adjustable torque arm after alignment. See Figure 3.
Figure 3
1.1.3.2
SINGLE POINT SUSPENSION & AIR SINGLE SUSPENSION
Single Point and some Air Spring suspensions are aligned during installation and welded
in place. If alignment is required, it is necessary to burn loose the inner and outer
adjusting bushing to realign.
Many Air Spring suspensions feature adjustable non-welded pivot bolts. Be sure to re-
torque these to recommended values after realignment.
Visual checks of these suspensions should be made periodically. Check the rubber
bushing on the end of the trunnion tube of single point suspensions. If frayed and torn
this could be an indication of loose “U” bolts.
1.1.3.3
ALIGNMENT PROCEDURE
1.1.3.3.1
Before taking axle alignment measurements, make sure the trailer is
unloaded and free the suspension of any “binds” by pushing the trailer
backwards and then pulling the trailer forward. While pulling the trailer
forward on a level floor, apply the brakes and release. This will assure that
an adjustable undercarriage is in its rearmost locked position. Trailers with air
ride suspensions shall be aligned with the suspension at its nominal ride
height. The trailer MUST be level from side to side as well as from front to
rear.
Note:
Neither service nor parking brakes should be applied during the
measurement procedure.
1.1.3.3.2
Use axle end extenders (or remove outer wheels and any obstructions) to
achieve a straight line for measuring from king pin to the axle ends.
1.1.3.3.3
Proper tools for axle alignment inspection are:
A. Spring loaded, kingpin extender with bubble level.
B. Axle end extenders.
C. 50 ft. steel tape.
D. Adjustable tram.
E. Gauge for measuring axle center to axle center.
Torque Arm Clamp Bolts