V
P
V
P

T72002 (HXL7), T72004 (HLS),
T72005 (HVS) 8, T72006 (HXL3) 8 and T72007
(HXL5) wheel-end maintenance procedures
available online. 4, 7

4
4
4
4
45

The above checks should be done any time suspension is damaged or otherwise NOT functioning properly.
V = Visual Check, P = Physical Check (operation, measuring, access, disassembly or other physical contact may be required), L = Lubrication Point.
For any inspection issues requiring service, refer to documents listed in the “Lit. No.” column, T15001 Air Ride Suspension Concepts and Functions or
contact Hendrickson for assistance. Also refer to PERIODIC INSPECTION SCHEDULE if adjustments are required.
Related literature for inspected items are available on the Hendrickson Trailer Suspension Literature web page at www.Hendrickson-intl.com/TrailerLit.
While under warranty, Hendrickson Technical Services must be contacted prior to hubcap removal and servicing.
A = Standard Service 1-year warranty wheel-end package), B = Extended-Life wheel-ends (HLS®, HVS®, HUS®, HXL3®, HXL5®, HXL7®).
NOTE: HUS is no longer available from its original supplier. If necessary, please contact Hendrickson for details.
For information on vendor components, contact the vendor directly. Links to ADB and wheel-end VENDOR LITERATURE is available at www.Hendrickson-intl.
com/TrailerLit.
If applicable and during warranty coverage of Standard 1-year, HVS and HXL3 wheel-ends; topping off oil to the hubcap fill line is allowed. The oil type
must be the same as originally filled by Hendrickson during suspension build. CONTACT HENDRICKSON for more details or questions.
Servicing of wheel-ends is not recommended while under warranty unless necessary and only after contacting Hendrickson Technical Services.

Table 1: Hendrickson trailer air ride suspension systems recommended inspection points and schedule

2

L578 H

Preventive Maintenance Guide
TABLE 1: INSPECTION

Lubrication
Same as Monthly. As a minimum requirement, all
lubrication points should be re-lubricated at this
interval, including slack adjusters.

Table 1 includes a list of recommended systems and
components to inspect, periodic inspection intervals
and related literature. For inspection procedures, refer to
the literature listed or manufacturer’s documentation.

Annually

INSPECTION/LUBRICATION INTERVALS
As stated on page 1, the following periodic intervals for
inspection and lubrication can be modified according to
trailer use. Inspection and lubrication may be required
more often if:
• Required by OEM.
• Required by component vendor; contact vendor.
• Trailer type and application demands are high.
• Impact or other evidence of suspension damage.

Inspection
Along with Monthly and Quarterly, perform annual
inspections listed in Table 1.
Lubrication
Same as Monthly.
ADB MAINTENANCE REQUIREMENTS
Proper care of ADB systems include regular inspections
and operational checks to include:
• Pad wear and retaining hardware (springs, bar, etc.).
• Protective covers (boots & caps).
• Mechanical movement and mating surfaces.

PDI
Pre-Delivery Inspections are typically required by
the trailer OEM to be conducted prior to new trailer
delivery to the customer. It should be performed by the
vehicle manufacturer or trailer dealer and includes
testing suspension and vehicle for proper operation.
This should also be performed by a repair facility after
replacing a suspension, slider box (AMBOX™) or axle/
beam weldment (HTRAAX™).

REFERENCES

Several Hendrickson and vendor references provide
inspection and lubrication information and details that
are beyond the scope of this document.
HENDRICKSON PUBLICATIONS
References to Hendrickson Trailer literature can be
found online at www.Hendrickson-intl.com/TrailerLit.
Click on the hyperlinked literature number, listed in
Table 1, to open.

Daily
This pre-operation inspection can detect worn, broken
or loose parts before any serious problems occur.
During a walk-around, check for any obvious problems
or abnormalities.

VENDOR LITERATURE
References to vendor literature and contact information
can be found online, starting at the vendor’s home
page. Some vendor literature is listed and linked in the
“Brake & Wheel-End Components” section of
www.Hendrickson-intl.com/TrailerLit.

Monthly
Inspection
This inspection is more comprehensive than the daily
inspection and covers more areas.

HT Y-BEAM INSPECTION

Seals, hubcap and hubcap gaskets should be checked
for condition and potential leaks.

Depending on application, operation and usage; the
HT™ Y-beam suspension may develop cracking in
the yoke area. Inspect Y-beams anytime maintenance
or service is performed on the trailer. CONTACT
HENDRICKSON if any cracking is found.

Lubrication
S-cam spider bushing and support bearing journal or
cam tubes should be greased at this time, plus during
any service when grease points are easily accessible.
Quarterly
Inspection
Along with monthly inspection, perform quarterly
inspections listed in Table 1.

L578 H

3

Flood Service Requirements

TYPE 1

(RECOMMENDED)

IDLE TIME

ITEMS TO CHECK

AFTER FLOOD 3

EVENT
COMMENTS

INSPECTION 4
Air springs
Brakes, Drum 2, 3
3

Brakes, ADB 2, 3 (Air Disc Brakes)
Brakes, Brake chamber actuator
Bushing tubes
Bushing tube spacers

3

Air line hoses, tubing, fittings, valves 3, etc.
Obvious signs of damage or wear
Shock absorbers
Wires, electrical connections and connectors

4 Inspect while aired up at ride height.
4
If submerged, replace caliper assemblies, otherwise inspect for
4
contamination and check function.
4 If submerged, replace brake chamber actuator.

V
V/P

4
4

V/P

4

V/P
V
V

4
4
4

V/P

4

4

V
V

4
4

4
4 Refer to L551 Shock Absorber Inspection Procedures.
If submerged, disassemble, clean and apply dielectric grease during
4
assembly.

V/P

Pests and insects will enter and nest in any small opening. Seals and
gaskets can dry and become non-functional.

SERVICE 4
Contamination
Lubrication 5
S-cam and cam tubes
Smooth wheel bearing rotation

V
V/P/L 4
P/L 4
4
P

5

Change hub seals, gaskets, lubricant 5 and axle filter
1
2
3
4
5

P/L

4 Where critical, remove all containments.
4 Ensure lubricant is fresh and moisture free at all grease fittings. Refer to
4 items (L) and relative literature column of Table 1 for more details.
If submerged, see line below.
Mandatory after flood, as needed after idle. Inspect axle interior for
4
moisture.

V = Visual Check, P = Physical Check (some disassembly may be required), L = Lubrication Point.
If drum or ADB rotor contact surface is corroded following flood and being submersed for any length of time, they must be replaced.
All systems should be operationally checked and tested.
Recommended checks before returning suspension to normal operation. Relative literature is listed in Table 1.
Replacing lubricant purges any collected moisture and/or degraded lubricant.

Table 2: Special event inspections & service

AFTER IDLE TIME OR FLOOD

Table 2 includes recommended inspections and service
for trailers that have been idle or submerged in water.
IDLE TIME
Trailer suspensions not operated (idle) for prolonged
periods of time must be inspected prior to renewed
operation (e.g. Trailer used for storage, etc.).
Normally, machined surfaces (bearing races, bearings,
etc.) are protected by lubrications flowing onto, over
and around during use. Lack of trailer motion causes
lubricants to flow downward and away from these
surfaces until it reaches a level pool in the hub. Metal
surfaces are eventually unprotected and exposed to the
environment.

Seals and gaskets not exposed to lubricant can degrade
in performance. Check and replace as needed.
Surface cracks on rubber components do not effect
performance. Refer to vendor for questions if needed.
FLOOD
Oil and water do not mix. Lubricants continue to seek a
level state, even while under water. All metal surfaces,
wires and materials that are directly exposed to
moisture, pollutants and other contaminants can lead to
rust and corrosion.
Refer to PERIODIC INSPECTION SCHEDULE for any
questions or issues relative to inspection or lubrication
or CONTACT HENDRICKSON.

Call Hendrickson at 866.RIDEAIR (743.3247) for additional information.
TRAILER COMMERCIAL VEHICLE SYSTEMS
2070 Industrial Place SE
Canton, OH 44707-2641 USA
866.RIDEAIR (743.3247)
330.489.0045 • Fax 800.696.4416

www.hendrickson-intl.com
L578 Rev H 11-18 ECN 32078

Rev G 10-18 ECN 31988

Rev F 04-18 ECN 31137

Rev E 09-17 ECN 30492

Hendrickson Canada
250 Chrysler Drive, Unit #3
Brampton, ON Canada L6S 6B6
800.668.5360
905.789.1030 • Fax 905.789.1033

Hendrickson Mexicana
Circuito El Marqués Sur #29
Parque Industrial El Marqués
Pob. El Colorado, Municipio El Marqués,
Querétaro, México C.P. 76246
+52 (442) 296.3600 • Fax +52 (442) 296.3601

Rev D 02-16 ECN 24754

Information contained in this literature was accurate at the time of publication. Product changes may have been made after the copyright date that are not reflected.

© 2018 Hendrickson USA, L.L.C. All Rights Reserved

Printed in United States of America