17730-299
13
Preventive Maintenance
ULTIMAAX
®
for Fire and Rescue Vehicles
SECTION 6
Preventive Maintenance
Following appropriate inspection procedures is important to help ensure the proper maintenance
and operation of the suspension system and component parts . Hendrickson recommends the
ULTIMAAX rear suspension be inspected at pre-delivery, the first in-service inspection and regu-
lar preventive maintenance intervals . Off-highway and severe service operating conditions may
require more frequent inspections than on-highway or less severe service operations . Inspection
must include the following items and other components referenced in this section .
NOTE
Torque values shown in this publication apply only if Hendrickson supplied fasteners are used . If
non-Hendrickson fasteners are used, follow the torque specification listed in the vehicle manufac-
turer’s service manual .
HENDRICKSON RECOMMENDED
INSPECTION INTERVALS
PRE-DELIVERY
INSPECTION
FIRST IN-SERVICE
INSPECTION
PREVENTIVE
MAINTENANCE
Inspect Progressive Load Spring
Within the first
500 Miles
(500 km)
Within the first
1,500 Miles
(2,000 km) or
100 Hours
Every 3 Months /
600 Hours
Inspect torque rods and equalizing beam end
connections
Every 6 Months /
1200 Hours
or
25,000 Miles /
40,000 km
Visually Inspect proper assembly and function . Check
for all of the following and replace components as
necessary:
• Signs of unusual movement, loose or missing
components
• Signs of abrasive or adverse contact with other
components (example: brake lines, wheel wells,
frame hangers, etc .)
• Damaged, or cracked parts
• Proper suspension function, alignment
Inspect fasteners for proper torque as recommended
in the Torque Specification Section of this publication
with special attention to the following suspension
connections:
• Equalizing beam end connection
• Saddle cap connection
• Frame hanger to frame rail connection
• Center Bushing
Every 12 Months /
2400 Hours
Verify the alignment of axles are within the vehicle
manufacturer’s tolerances .
COMPONENT INSPECTION
Following appropriate inspection procedures is important to help ensure the proper maintenance
and operation of the ULTIMAAX heavy-duty rear suspension system and component parts . Look for
and replace worn, damaged, bent or cracked parts .
■
Cross tube —
Clean the cross tube and inspect it for cracks or excessive wear 8" to 10" from
each end where it enters into the equalizing beam center bushings . Use a straight edge to
check the straightness of the cross tube . If there is a doubt as to fracture, wear or straightness,
replacement is necessary .