Ridewell Suspensions RAR-251 Manual

251-Trailer-ISM 09-13-18 Page 1 ENG
Suspension Identication..................................... 2
Suspension System/Axle Serial Tag
Installation ............................................................. 3
Prior to Installation
Axle Integration
Axle Weld Standards
Suspension Mounting
Torque Specications
Maintenance .......................................................... 8
Recommended Service Intervals
Parts Illustration
RAR-251 - ADB Assembly
Pivot Bushing Replacement Procedure
Lower Beam Assembly - Bearing Replacement Procedure
Warranty............................................................... 12
Part No.: 9710119
Doc:
251-Trailer-ISM 09-13-18
RAR-251 - Stub Axle Suspension
Trailer Air-Ride Suspension
Installation and Service Manual

ENG Page 2 251-Trailer-ISM 09-13-18
Gross Axle WeiGht rAtinG CertifiCAtion is per the finAl stAGe
mAnufACturer or Alterer.
this produCt mAy be Covered under one or more pAtents.
AdditionAl pAtents mAy be pendinG.
for more informAtion on pAtent or suspension/Axle CApACity rAtinG
ContACt rideWell CorporAtion.
www.ridewellcorp.com [phone]
PART NO:
SERIAL NO:
Figure 1.
The Suspension Serial Tag is located on the left-
hand (driver’s side) suspension hanger.
MODEL: PART NO.
SERIAL NO. CAPACITY TON
Introduction
The Ridewell Air Ride (RAR) 251 Trailer Suspension
is designed for use in a range of applications. The
suspension can be purchased with or without an inte-
grated stub-axle.
The mounting hardware kit enclosed with the sus-
pension is designed for a basic vehicle installation
that accommodates up to 5/8”-thick hanger side
plates. Ridewell can design a suspension hanger for a
specic application.
Read through the entire Installation and Service
Manual (ISM) before performing any installation or
maintenance procedures.
Identication Tag
Ridewell suspension systems and axles can be identi-
ed by the Part Number and Serial Number listed on
the serial identication tags.
Suspension Serial Tag
The Suspension Serial Tag provides information on
the suspension model (Figure 1).
The Part Number (251xxxx) refers to the individual
model of the suspension system.
The nine-digit Serial Number (1xxxxxxxx) refers to
the date and order of manufacture of the suspension.
Please refer to both the part number and serial num-
ber when contacting Ridewell for customer service,
replacement parts and warranty information.
Axle Body - Serial Tag
Ridewell-branded axles have an axle body serial tag
listing the Base-Axle Part Number (165xxxx) and the
Serial Number of the axle tube (Figure 2).
Notes and Cautions
All work should be performed by a properly trained
technician using the proper/special tools and safe
work procedures.
The ISM uses two types of service notes to provide
important safety guidelines, prevent equipment dam-
age and make sure that the suspension system oper-
ates correctly. The service notes are dened as:
“NOTE”: Provides additional instructions or
procedures to complete tasks and make sure that
the suspension functions properly.
Indicates a hazardous situation or
unsafe practice that, if not avoided, could result
in equipment damage and serious injury.
SUSPENSION IDENTIFICATION
Figure 2.
Ridewell axles have a serial identication tag listing
the Base Axle Part Number (165xxxx) and the
Serial Number of the axle body.

251-Trailer-ISM 09-13-18 Page 3 ENG
INSTALLATION
Installer Responsibilities
The installer of the suspension has the sole responsi-
bility for proper aachment of the suspension system
to the vehicle chassis.
• The installer is responsible for locating the sus-
pension system on the vehicle to provide the
proper load distribution.
• The installer must verify that vehicle crossmem-
bers are positioned to support the suspension at
the installing location.
• It is the installer’s responsibility to determine that
axle spacing conforms to any applicable federal
and local bridge laws.
• The installer must verify that air reservoir volume
requirements are met after suspension installa-
tion. Consult the vehicle manufacturer or Federal
Motor Vehicle Safety Standards (FMVSS) 121 for
more information.
• The installer must verify there is sucient clear-
ance for proper functioning of the suspension, air
springs, brake chambers, axle and tires.
Prior to Installation
Refer to the engineering drawing to conrm dimen-
sional requirements and the range of ride heights
available.
Installations can vary and procedures should be
adapted for dierent vehicles, as needed.
• The Gross Axle Weight Rating (GAWR) is deter-
mined by the system component with the lowest
load rating. Please consult with tire, wheel, axle
and brake manufacturers before installation to
determine the GAWR.
• If vehicle chassis modications are required, con-
sult with the vehicle manufacturer to ensure that
such changes are permied.
• Welding or altering suspension components
is not permied without the express wrien
permission of Ridewell Suspensions.

ENG Page 4 251-Trailer-ISM 09-13-18
Figure 3.
Axle should be centered on beam. Refer to the en-
gineering drawing for measurements.
Figure 4.
Correct axle tube seating for welding.
Axle Integration
Suspension systems are available with and without
a factory integrated axle. Customer-supplied axle
assemblies must be positioned and oriented (rotated)
properly before welding the axle to the axle seats.
Use the top-center mark on the axle, if available, to
identify the center of the axle and orient the axle as-
sembly on the suspension. The axle assembly should
be installed so that the camshafts, when activated,
rotate in the same direction as the wheels.
Failure to follow procedures and design
specications could result in injury, damage to the
axle or suspension and void the warranty.
Weld Preparation
The joint to be welded should be positioned in the
at or horizontal position. All grease, dirt, paint, slag
or other contaminants must be removed from the
weld joint.
The axle and suspension components should be at a
minimum temperature of 60°F (15.5°C). Pre-heat the
weld zone to the axle manufacturer’s recommended
pre-heat temperature, if required.
Weld Procedure
1. Center the axle assembly on the beam centers
(Figure 3).
2. Check the engineering drawing for the brake
component orientation (rotation) before clamping
into place and making the nal welds.
2.1 Drum brake camshafts are spaced o the tail
of the trailing arm beam. Make sure the brake
chamber brackets are oriented properly and
clamp the axle assembly into place.
2.2 Disc brake assemblies have a right- and
left-hand caliper assembly. Make sure the
callipers are located on the correct side and
rotated to the proper position before clamping
the axle assembly into place.
3. Check the gap between the axle and the axle seats
before welding (Figure 4). Side gaps should be
no greater than 1/8”. The gap at the boom of the
axle seat should be no greater than 1/16”.
4. Weld the axle to the seat according to Ridewell
Weld Process #1 (Page 5).

251-Trailer-ISM 09-13-18 Page 5 ENG
SHEET OF
RIDEWELL CORPORATION
PO BOX 4586 SPRINGFIELD, MISSOURI 65808
A-SIZE:
SCALE:
MATERIAL:
PROJECT NO:
APPROVED:
DRAWN BY:
CHECKED:
TITLE:
WEIGHT:
R
REV:
PART NO:
WELD PROCESS #1
RIDEWELL WELD PROCESS #1,
5" DIA. AXLE, 3 PASS WELD
CBC
2/1/2016
MDJ 2/21/2003
CJB 2/21/2003
03103
11
--
NTS
WELD JOINT PREPARATION FIRST PASS SECOND PASS THIRD PASS
3.0°
4.0°
NO WELD
TOP OF AXLE
NO WELD
BOTTOM
OF AXLE
NO WELDING ZONE
SMAW GMAW / FCAW
AXLE
BEAM AXLE SEAT
AXLE
BEAM AXLE SEAT
AXLE
BEAM AXLE SEAT
1/8" MAX
REPRESENTATIVE AXLE SEAT (PROFILE DEPENDENT ON SUSPENSION PRODUCT)
ARC STOP
ARC START
ARC STOP
ARC START
AXLE
BEAM AXLE SEAT
1.0 TYP 1.0 TYP
FIRST PASS FIRST PASS
SECOND PASS SECOND PASS
THIRD PASS THIRD PASS
REV PROJECT DESCRIPTION DATE BY CHK APPD
3/8"
ROOT
PASS
THIRD
PASS
1/2"
1/2"
SECOND
PASS
E 15101
REVISED TEXT. REMOVED LIST OF MODELS.
6/30/15 G.H. MDJ CJB
1- CAUTION: All welds must be kept away from the top and bottom of the axle where maximum stresses occur
(see “NO WELDING ZONE” illustration above). Do not test-weld the arc on any part of the axle tube.
2 - All welders and welding operators should be certified as per the requirements of the American Welding Society (AWS)
or equivalent. All electrodes used should meet the AWS specifications and classifications for welding carbon
and low-alloy steels.
3 - Recommended Welding Methods: Shielded Metal Arc Welding (SMAW), Gas Metal Arc Welding (GMAW) or Flux
Cored Arc Welding (FCAW). The welding method used and the electrode selected must develop a minimum weld
tensile strength of 70,000 psi per AWS specifications. The best fusion and mechanical properties will be obtained by
using the voltage, current, and shielding medium recommended by the electrode manufacturer. If the SMAW method
is used, the stick electrodes must be new, dry, free of contaminants and stored per AWS specifications.
4 - Weld Joint Preparation: The joint to be welded should be positioned in the flat or horizontal position. All grease, dirt, paint,
slag or other contaminants must be removed from the weld joint without gouging the axle tube. CAUTION: Never weld
when the axle is cold. The axle and beam assemblies to be welded should be at a temperature of at least 60°F (15°C).
Pre-heat the weld zone to the axle manufacturer's recommended pre-heat temperature, if required. This will reduce
the chance of an area of brittle material forming adjacent to the weld.
5 - The axle should fit into the beam assembly with a maximum root gap of 1/8-inch between the axle and the beam axle seat
(see “WELD JOINT PREPARATION” illustration above).
6 - NOTE: Clamp the axle to the beam axle seat with a C-clamp prior to welding to make sure that proper contact occurs
(see “CORRECT” illustration below).
7 - Ground the axle to one of the attached axle parts such as the brake chamber brackets, cam brackets or brake
spider. Never ground the axle to a wheel or a hub as the spindle bearing may sustain damage.
8 - Multiple pass welding should be used on the beam/axle connection using the following guidelines: 8.1-Total fillet weld size
should be 1/2-inch. 8.2-Weld pass starts and stops should be performed as illustrated above. 8.3-Never start or stop welds
at the end of the weld joint. 8.4-Each pass must be accomplished in one or two segments. 8.5-Start welds at least 1-inch
from the end and backweld over the start. Backstep fill all craters. 8.6-If process is not GMAW all slag must be removed
between passes.
8.7-Welds must go to within 1/8-inch +/- 1/16-inch of the ends of the axle seat and must not go beyond or around the ends
of the axle seat. 8.8-Post-weld peening is recommended, but not required: Needle peen the entire toe of the second pass,
including around the ends of the axle seat. Hold the needles perpendicular to the axle. A uniform dimpled pattern
will appear when properly peened.
F 16101
ADDED MAXIMUM TO 5, ADDED GMAW NOTE TO 8.6
2/10/2016 G.H. B.B. CJB
UPDATED CORRECT VIEWS
F

ENG Page 6 251-Trailer-ISM 09-13-18
Mounting the suspension to the frame
Refer to the engineering drawing for the range of ride
heights available, torque values, spacing and clear-
ance requirements of the suspension.
Frame hangers are an optional component of the
RAR-251 Trailer Suspension. Ridewell can design a
suspension hanger for a specic application.
It is the responsibility of the trailer OEM to design
a hanger and alignment mechanism that ts to the
trailer frame.
The suspension installer has the nal responsibility
of aaching the suspension to the vehicle frame.
(Optional Hanger) Weld-On Installation
Check that the location provides adequate clearance
for suspension components.
Hangers and air spring mounting plates should be
perpendicular to the chassis frame and in alignment
with each other.
1. Mark the desired location of the hangers on
the vehicle frame. Hangers must be installed as
shown on the engineering drawing for proper
axle alignment.
2. Weld the hangers to the frame with 1/4” llet
welds completely around the hangers. Stop the
welds 1/2” from the corners and edges.
3. Mark the desired location of the air spring
mounting plates on the frame. A minimum 0.75-
inch clearance must be maintained around the air
spring when it is at maximum diameter.
4. Weld the air spring mounting plates to the frame
with 3/16” llet welds.
Stub axle suspensions are designed with a roll joint.
Roll stops are not provided in this suspension. Tire
rub plates must be installed on the trailer frame to
limit roll to 10-degrees or less.
Final Assembly and Inspection
• Verify the welds of the hanger and air spring
mounting plates.
• Brake chamber clamps and ports must be clocked
(rotated) to prevent interference with surround-
ing components.
• Aach pivot assemblies to hangers.
Note: Do not fully torque pivot hardware until
axle alignment is completed.
• Installer must set the suspension to the specied
mounting height before torquing the pivot bolt to
prevent pre-loading the rubber in the bushing.
• Dowel pin must be installed in roll joint before
welding on anti-turn washer. Anti-turn washer
must cover dowel pin.
• Refer to engineering drawing to install shock
absorber. Torque to specications (Page 7).
• Complete assembly and installation of air springs
as shown on the engineering drawing. Torque to
specications (Page 7).
• Install/connect the height control valve (HCV), if
applicable. Check the air system tubing and t-
tings after installation for leaks.
• Verify the suspension ride height is adjusted
within the range shown on the engineering draw-
ing and complete axle alignment procedure.
The Limiter Chain connection point shown on the
drawing is for reference only. Locate the chain so that
chain can not interfere with the axle assembly, the
brake chambers or the wheels or tires.
Frame tab should be placed after suspension installa-
tion and with the suspension in full rebound posi-
tion. Limiter Chain must be travel limiter.
Failure to torque bolts/nuts of suspension
components to specications can result in failure of
the suspension and void the warranty.

251-Trailer-ISM 09-13-18 Page 7 ENG
RAR-251 Trailer Suspension - Torque Specications
Fastener Type Size
Torque Values
foot-pound Newton-meter
Center Bolt (HHCS) - Lower Beam Assembly 1 1/4”-7NC
750 ft-lb 1017 N-m
Pivot Bolt/Pivot Nut (Pivot Assembly) 1”-14NF
500 ft-lb 678 N-m
Nut (Air Spring) 3/4”-16NF
50 ft-lb 68 N-m
Bolt (Air Spring) 1/2”-13NC
25 ft-lb 34 N-m
Bolt/Locknut (Shock Absorber) 3/4”-10NC
160 ft-lb 217 N-m
Bolt/Locknut (Gimbal-Shock Absorber) 1/2”-13NC
80 ft-lb 108 N-m
Torque values reflect a lubricated thread condition (Nuts are pre-lubed). Do not overtorque.
Suspension is shipped with minimal torque applied to fasteners. It is the installer’s responsibility to
apply the proper torque values. Failure to install and maintain fasteners at torque specifications could result in
suspension failure and voiding of the warranty. Refer to the engineering drawing for torque specifications.

ENG Page 8 251-Trailer-ISM 09-13-18
MAINTENANCE
A visual inspection of the suspension structure should be performed during each pre-trip/safety inspection.
Ridewell Suspensions recommends the following minimum service intervals for standard duty, on-highway
usage applications. More frequent intervals are recommended for heavier duty applications.
Daily/Pre-Trip Inspections
___ Check tires for proper ination, damage or
excessive wear.
___ Check wheel-ends for obvious signs of lubricant
leakage. Check for missing components.
___ Check axle assemblies for damage or loose
components.
___ Visually inspect suspension structure for signs
of damage or excessive wear.
___ Check for loose or missing bolts/nuts. Check for
irregular movement in suspension components.
___ Make sure air controls are operating properly.
Drain all moisture from air reservoirs.
First 6,000 miles of use
___ Torque all suspension component bolts/nuts to
specications (Engineering drawing).
___ Verify that the suspension is operating at the
installed ride height.
Every 12,000 miles of use
___Inspect air springs for any damage or excessive
wear. Torque air spring bolts/nuts to specications
(Engineering drawing).
___ Check air lines and connections for leaks.
Every 50,000 miles of use
___ Torque all suspension component bolts/nuts to
specications (Engineering drawing).
Annually/100,000 miles of use
___ Inspect pivot connection for worn pivot bushing
and wear washers. Replace components, if neces-
sary. Torque suspension component bolts/nuts to
specications (Engineering drawing).
___ Check arm beam-to- axle connection welds.
___ Check lubrication level in wheel ends:
1) Oil-Filled Wheel Ends:
Refill/Replace lubricant as needed (Refer to
TMC RP 631 “100K/Annual Inspection”).
2) Semi-Fluid Grease:
Pull outer bearing and visually inspect lubrica-
tion level. Rell/Replace as needed
(Refer to TMC RP 631 “Level 3 Lubrication Level
Inspection” and TMC RP 618 “Wheel Bearing
Adjustment Procedure”).
___ Check air lines and connections for leaks.
___ Test air control system pressure protection valve
(PPV), if equipped.
___ Check height control valve (HCV) adjustment.
___ Verify that the suspension is operating at the
installed ride height.
Failure to torque the bolts/nuts of suspen-
sion components to specications can result in failure
of the suspension and voiding of the warranty.
Refer to the following Technology &
Maintenance Council (TMC) publications
for additional maintenance information:
TMC RP 609 Self-Adjusting and Manual Brake
Adjuster Removal, Installation
and Maintenance
TMC RP 618 Wheel Bearing
Adjustment Procedure
TMC RP 619 Air System Inspection Procedure
TMC RP 622 Wheel Seal and Bearing Removal,
Installation, and Maintenance
TMC RP 631 Recommendations for
Wheel End Lubrication
TMC RP 643 Air Ride Suspension
Maintenance Guidelines
TMC RP 728 Trailer Axle Maintenance

251-Trailer-ISM 09-13-18 Page 9 ENG
Figure 5.
RAR-251 Trailer Suspension for stub axle (Air Disc Brake Assembly shown).
Refer to the engineering drawing for the component part number.
Thrust Washer
Shim(s)
Composite Bearing
Air Spring
Pivot Assembly
(Optional hangers shown)
Pivot Bolt
Flat Washer
Alignment Washer Stub Axle
Disc Brake Assembly
Lower Beam Assembly (LBA)
(One of two)
Bolt
Lock Washer
(Air Spring)
Nut
(Air Spring)
Upper Bracket Mount
Bolt/Locknut
Composite Bearing
Thrust Washer
Limiter Chain Attachment
(Drum Brake)
Pivot Nut
Flat Washer
Alignment Washer
ADB Axle-
Limiter Chain Attachment
Bolt
Anti-Turn Washer
Dowel Pin
End Cap
Lower Bracket Mount
(Shock Absorber)
Locknut
Tube-Shock Gimbal
Gimbal Sleeve
Tube
Flat Washer
Bolt
Shock
Absorber
Pivot
Bushing Gimbal Mount

ENG Page 10 251-Trailer-ISM 09-13-18
RAR-251 Trailer Suspension – Pivot Bushing Replacement Components
Replacement
Part Numbers Hardware Description
Torque Values
foot-pound Newton-meter
11400016
1150031 Pivot Bolt (HHCS) 1”-14NF (Grade 8) Pivot Nut 500 ft-lb 675 N-m
1110088 Spherical Bushing
7002768 Alignment Washer
1161480B100 Flat Washer
Lower Beam Assembly (LBA) – Bearing Replacement Components
1145923B105 Center Bolt (HHCS) 1-1/4”-7NC 750 ft-lb 1017 N-m
1120045 Composite Bearings for Pivot Assembly
1160022 Thrust Washer 1/4
7002339 End Cap
7002747 Shim, End Cap
9280042 Dowel Pin
9003092B000 Anti-Turn Washer
Failure to install and maintain suspension component fasteners at torque specifications could result in
suspension failure and void the warranty. Refer to the engineering drawing for torque values.
Figure 6.
Bushing replacement should include components for two pivot connections (one pivot assembly) on each
axle. Pivot bushings should be replaced in both pivot connections at the same time.
Lower Beam Assembly (LBA)
(One of two)
Thrust Washer
Shim(s)
Composite Bearing
Composite Bearing
Thrust Washer
Bolt
Anti-Turn Washer
Dowel Pin
End Cap
Pivot Assembly
(Optional hangers shown)
Pivot Bolt
Flat Washer
Alignment Washer
Pivot Bushing
Pivot Nut
Flat Washer
Alignment Washer
Limiter Chain Attachment
(Drum Brake)
Lower Bracket Mount
(Shock Absorber)