215T-Trailer-ISM-RevC-06-06-18
Page 7
ENG
Final Assembly and Inspection
1. Verify welds of frame hangers and air spring
mounting plates.
2. Inspect for any loose or missing fasteners on the
suspension assembly. Verify that all suspension
component bolts/nuts are torqued to proper val-
ues (Appendix).
3. Install wheels and tires.
When lowering an auxiliary axle on an
unloaded vehicle, pressure to the load air springs
must be reduced to below 10 psi. Failure to
reduce the air pressure could cause the vehicle’s
drive axles to rise from the ground and the ve-
hicle could roll in an unsafe manner.
4.
Check that tires are inflated to recommended
pressure. Check wheel hubs for proper level of
lubricant recommended by the manufacturer.
5. Lift the axle to the raised position. Check the air
system tubing and connections for leaks.
6. Check that wheels can rotate freely and that
brakes and slack adjusters are properly adjusted.
7. Raise and lower the suspension assembly (wheels
and tires installed) through the entire range of
travel. Make sure that sufficient clearances for air
springs, brake chambers and other components
has been provided.
Do not lower the auxiliary axle while the
vehicle is moving above 10 mph.
Regulate load with air spring pressure
The load capacity of the auxiliary axle is ad-
justed by increasing or decreasing the pressure
to the air springs. By applying more air, the lift
axle takes on a greater percentage of the load’s
weight. The load capacity is decreased as the air
pressure decreases.
Accurate readings of the load capacity can be
obtained by parking a loaded vehicle over a
calibrated scale and lowering the axle onto the
scale. The air pressure to the air springs is manu-
ally adjusted up or down to obtain the axle load
weight at various air pressures.
Do not exceed the rated load capacity of
the suspension system or other components. Ex
-
ceeding the capacity can cause component failure
and void the warranty.
