Great Dane 42101401 - Manual (Page 16)

The shock absorbers should be replaced at the first
sign of leaking hydraulic fluid. Worn shocks will allow
tire hop and yield poor handling characteristics.
Many air suspensions are equipped with air control
kits. The air control kit allows the raising or lowering
of the vehicle bed by inflating or exhausting air from
the air suspension. Do NOT operate the vehicle when
the suspension is in the lowered or raised position.
Improperly maintained air suspensions will result in
trailer suspension damage which includes bushing
wear and irregular tire wear.
By customer specification, Great Dane may have
installed any of the following air-spring suspensions on
your new trailers.
Neway A.R. models
Reyco 86 A.R. models
Hendrickson models
Meritor models
Tuthill models
Please reference the bibliography in the back of the
manual to obtain address for ordering manufacturer-
specific maintenance manuals.
LEAF-SPRING SUSPENSION
Check the torque of all suspension bolts after initial
break-in period on the road and thereafter at regular
intervals not to exceed 25,000 miles. Follow the
torquing recommendations of the suspension
manufacturer. If they are not available, use the follow-
ing table of torque recommendations for clean dry
threads. The use of lubricants will apply more tensile
force for the same torque. If lubricants are used,
decrease torque approximately 30%.
1" 14 UNC 350 - 375 lb-ft
7/8" 14 UNF 275 - 300 lb-ft
5/8" 18 UNF 75 - 90 lb-ft
5/8" 18 UNF 125 - 155 lb-ft (step bolts)
1/2" 45 - 50 lb-ft
It is especially important to maintain torque on U-bolts,
equalizer bolts, and torque arm bolts. Torque the nut
side of torque arm bolts only. Torquing the bolt heads
will not produce the desired clamping force.
RUNNING GEAR ASSEMBLY
Inspection of upper running gear rail weld attachment
to the trailer for weld fatigue cracks is a requirement of
the annual FHWA inspection. All trailer structures
should be inspected for weld fatigue cracks and/or
loose fasteners and any found should be corrected as
a part of routine PM (preventative maintenance) serv-
ice. Any defects in a trailer should be corrected to the
manufacturer specifications before the trailer is
returned to service.
FIXED SUSPENSION
1. If the trailer is equipped with a fixed suspension,
visually check all bolts connecting the suspension
frame assembly to the upper running gear rails.
2. If these bolts need replacing, use only Grade 5
(minimum) bolts with Grade B (minimum) locking-
type nuts. Be careful in selecting the proper bolt grip
length so that threads are not at the interface of the
rail/frame joint.
SERVICING RIMS & WHEELS
For information on servicing wheels and rims, refer to
OSHA 29 CFR 1910.177 and to the appropriate wheel
and rim manufacturer’s manuals. Also refer to
“Servicing Single-Piece and Multi-Piece Rim Wheels,”
U.S. Department of Labor pamphlet, OSHA 3086 and
the accompanying two chart set, available from OSHA
regional offices.
NOTICE: Loose U-bolts can produce spring
damage. Improperly torqued bushing bolts can
produce premature bushing wear.
14
WARNING Tire and wheel/rim servicing can be
extremely dangerous and must be done only by
trained personnel using proper tools and proce-
dures. Information about tire and wheel servicing
can be obtained from:
US Department of Labor
OSHA Publications Office
Room N-3101
Washington, DC 20210
Telephone: 202-523-9667
NHTSA
Auto Safety Hotline
400 7th Street SW
Washington, DC 20590
Telephone: 800-424-9393
DANGER Tires must only be inflated while in a
restraining device/safety cage.