NHTSA ID Number: 10126523
Manufacturer Communication Number: L1055, Rev. E
TSB/Document Date: 2017-12-22
Summary
Operation Name: Hendrickson
Trailer Commercial Vehicle Systems Document Name: Parts List - SURELOK Summary: This document provides parts lists for Hendrickson SURELOK ride height lock mechanisms.
S-21766-5
S-21766-6
S-21766-7
S-21766-8
3
AIR SPRING ACTUATOR ASSEMBLY
S-25593
1
SLKN and SLKR models; Includes air spring
actuator and 2 speed nuts
4
BRAKE CHAMBER (Not shown)
A-21452
1
SLKC and SLKM models; Type 9 chamber
5
BEAM EXTENSION WELDMENT (Not shown)
SLKR models
C-21442
2
SLKM models
C-26363
2
6
SPRING
1.25" × 6.125" × .177" (Not shown)
S-21539
1
SLKC and SLKM models
1.50" × 6.63" × .177"
B-26597
1
SLKR and SLKN models
7
SHAFT BRACKET
S-36137
2
8
MOUNTING HARDWARE FOR SHAFT BRACKET
1/2" - 13" flanged screw
SA-6900-10
4
1/2" - 13" prev-torq HEX FLG Nut
SA-7000-1
4
3/8" - 16" flanged screw
SA-6900-5
4
3/8" - 16" prev-torq HEX FLG Nut
SA-7000-3
4
SPEED NUT
A-24482-1
2
9
10
2 per bracket
MOUNTING HARDWARE FOR BRAKE CHAMBER (Not shown)
L1055 Rev E
9
SLKC and SLKM models
SLKN and SLKR models
SURELOK PARTS LIST
®
HT™ SERIES HT190 / 230 Top-mount Suspensions
ITEM
1
DESCRIPTION
SURELOK® RETROFIT KIT1 (Not shown)
SLKU_- XXX
SURELOK SERIES
SLKL
SLKQ
SLKK
SLKA
2
SYSTEM
QTY.
PART NO.
Long Beams
Short Beams
Long Beams
Short Beams
NOTE
1
Please contact Hendrickson for assistance
SUSPENSION MODEL
High Control
Standard
RIDE HEIGHT LOCK ASSEMBLY
Slider Box Width
14.0" ride height
15.0" ride height
16.0" ride height
17.0" ride height
14.0" ride height
15.0" ride height
16.0" ride height
17.0" ride height
42" Box
BRAKE CHAMBER ACTUATED (SLKL and SLKQ)
S-23630-1
S-23630-3
S-23630-5
S-23630-7
BRAKE CHAMBER ACTUATED (SLKA and SLKK)
S-21443-1
S-21443-2
S-21766-1
S-21443-4
48" Box
S-23630-2
S-23630-4
S-23630-6
S-23630-8
S-21443-5
S-21443-6
S-21766-5
S-21443-8
3
A-21452
1
Type 9 chamber
4
BEAM EXTENSION WELDMENT (Not shown)
C-26363
2
SLKA and SLKQ models
5
BEAM EXTENSION SCREW (Not shown)
SA-6900-8
2
6
SPRING
S-21539
1
1.25" × 6.125" × 0.177"
2
3
6
10
L1055 Rev E
SURELOK PARTS LIST
®
HT™ SERIES HT250US Underslung Suspensions
ITEM
1
DESCRIPTION
SURELOK® RETROFIT KIT1 (Not shown)
SURELOK SERIES
SLKU
2
PART NO.
SYSTEM
QTY.
SLKU_- XXX
1
NOTE
Please contact Hendrickson for assistance
SUSPENSION MODEL
HT SERIES Underslung HT250US
RIDE HEIGHT LOCK ASSEMBLY
Slider Box Width
42" Box
BRAKE CHAMBER ACTUATED (SLKU)
D-27888-1
D-27888-2
12.0" ride height
14.0" ride height
48" Box
D-27888-3
D-27888-4
3
S-23169
1
Type 12 chamber
4
SPRING
S-21539
1
1.25" × 6.125" × 0.177"
5
GREASE FITTING (Not shown)
S-22830
4
3
3
2
4
L1055 Rev E
11
SURELOK PARTS LIST
®
HS SERIES HS190 / 230 Slider Suspensions
ITEM
1
DESCRIPTION
SYSTEM
QTY.
SLK_-XXX
1
SURELOK® RETROFIT KIT1 (Not shown)
SURELOK SERIES
SLKB
SLKA
2
PART NO.
NOTE
Please contact Hendrickson for assistance
SUSPENSION MODEL
Long beams
HS models
Short beams
RIDE HEIGHT LOCK ASSEMBLY
Slider Box Width
14.0" ride height
15.0" ride height
16.0" ride height
17.0" ride height
42" Box
BRAKE CHAMBER ACTUATED (SLKB AND SLKA)
S-23630-1
S-23630-3
S-23630-5
S-23630-7
48" Box
S-23630-2
S-23630-4
S-23630-6
S-23630-8
A-21452
1
Type 9 chamber
4
SPRING
S-21539
1
1.25" × 6.125" × 0.177"
5
MOUNTING HARDWARE (Not shown)
1/2" - 13" flanged screw HTES-1057
SA-6900-8
2
SLKA models
1/2" - 13" × 100 lg. flanged bolt
SA-6900-6
8
SLKB models
1/2" - 13" prevailing torque flanged nut
SA-7000-1
8
SLKB models
BEAM EXTENSION
C-26363
2
SLKA models
3
6
3
3
2
4
12
L1055 Rev E
SURELOK PARTS LIST
®
SURELOK AIR CONTROL KITS
®
ITEM DESCRIPTION
1
2
3
4
5
6
7
PART NO.
SYSTEM
QTY.
Manual Bypass – allows you to completely bypass SURELOK®, meaning the legs are disengaged and not functioning.
3-WAY BALL VALVE (Not shown)
VS-22535
1
Manual Bypass with Dump – allows you to completely bypass SURELOK and fully exhaust the trailer’s air suspension.
3-WAY BALL VALVE
VS-22535
1
3-WAY AIR PILOTED VALVE (Not shown)
VS-23588
1
2-WAY CHECK VALVE (Not shown)
VS-24988
1
Specialized Auto Dump – AKSL0001 – Allows SURELOK to engage, then exhausts the trailer’s air suspension to rest the
SURELOK legs on the suspension beams.
3-WAY PILOT VALVE (Not shown)
VS-24053
1
CHOKE (Not shown)
A-27314-1
1
1/8" NPT
Manual Bypass with Specialized Auto Dump – Allows you to completely bypass SURELOK, OR allows SURELOK to engage,
then exhausts the trailer’s air suspension to rest the SURELOK legs on the suspension beams.
3-WAY BALL VALVE (Not shown)
VS-22535
1
SURELOK
SURELOK
®
®
BYPASS
BYPASS & DUMP
NORMAL
NORMAL
RESERVOIR
2
PRESSURE
PROTECTION
VALVE
EMERGENCY
AIR
COMMON PORT
SURELOK
ACTUATOR
L1055 Rev E
13
SURELOK PARTS LIST
®
NOTES
14
L1055 Rev E
SURELOK PARTS LIST
®
L1055 Rev E
15
Call Hendrickson at 330.489.0045 or 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
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
L1055 Rev E 10-17
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.
© 2017 Hendrickson USA, L.L.C. All Rights Reserved
Printed in United States of America
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TSB/Document ID: L1055, Rev. E
Replacement Service Bulletin Number:
MFR Communication Date: 2017-10-01
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: SUSPENSION
MFR Component System:
MFR Component Subsystem:
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