TRUCK SERVICE MANUAL
SPRINGS
and brackets. Rear ends of springs have no rigid
attachment to spring brackets, but are free to move
forward and backward to compensate for spring
deflection.
The equalizing beams utilize the "lever" principle to
distribute the load equally between axles and to reduce
the effect of bumps and road irregularities. The torque
rods permit complete absorption of torque, which is the
tendency of the axles to turn backwards or forward on
their axis due to starting or stopping inertia. The cross
tube connecting the equalizing beams assures correct
Fig. 1. Tandem Axle with Equalizing Beam
alignment of the tandem and prevents damaging load
Suspension
transfer.
DESCRIPTION
Tandem drive axles require a special suspension
which permits flexibility between the axles but still
withstands rugged usage with long service life. The
equalizing beam type suspension system described
herein embodies these required characteristics. Types
of equalizing beam suspensions used on IH trucks are:
leaf spring type and rubber load cushion type. Air spring
type, which uses rubber air bags in place of springs, is
available as optional equipment.
Leaf Spring Type
The leaf spring type suspension (Fig. 2) uses semi-
elliptic leaf springs to cushion load and road shocks.
The springs are mounted on saddle assemblies above
the equalizer beams and are pivoted at the front end on
spring pins
Fig. 2. Equalizing Beam Suspension
Leaf Spring Type)
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