Ridewell Suspensions RAR-240 User manual

RAR-240 Series
Trailer Air-Ride Suspensions
Owner’s Manual
www.ridewellcorp.com
P.O. Box 4586 zSpringfield, MO 65808 z417.833.4565 z417.833.4560 (fax)
0711

Suspension Identification:
Parts:
Sales, Service & Warranty:
Ridewell Suspensions are identified by a metal tag attached to the left-hand hanger that indicates part
number, revision level, & serial number.
For optimum suspension performance, order only Ridewell parts. Replacement parts for RAR-240 are
shown on pages 13-16 of this manual.
If you need assistance regarding this product, please contact us and we will be glad to help you.
Mailing Address
Ridewell Corporation
P.O. Box 4586
Springfield, MO 65808
Shipping Address
Ridewell Corporation
3715 East Farm Rd. 94
Springfield, MO 65803
Phones, Fax, E-mail
800.641.4122, 417.833.4565
417.833.4560 (fax)
[email protected]

RAR-240 Owner’s Manual
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Contents
Pre-InstallationNotes...................................................................................................................3
Configuration...................................................................................................................4
Installation - General...........................................................................................................4
Installation - Axle to Suspension.........................................................................................5
Installation - Suspension to Frame......................................................................................5
Axle Alignment...................................................................................................................6
Torque Requirements..........................................................................................................8
Height Control System Installation.....................................................................................9
Bushing Check Procedure....................................................................................................9
Bushing Replacement Procedure...................................................................................10-11
WeldProcess.......................................................................................................................12
Parts Illustrations.........................................................................................................13-16
MaintenanceSchedule.........................................................................................................17
Warranty.........................................................................................................................17
Pre-Installation Notes
1. Suspensions are designed to operate within specific parameters. Operating the suspension
outside the design paramaters may result in improper performance, damaged equipment,
and voiding of the warranty.
2. e total operating capacity of a suspension / running gear system is determined by the
component with the lowest road rating. Please consult with the manufacturers of axles, brakes,
tires and wheels to determine the maximum suspension system capacity.
3. e installer is responsible for ensuring that air volume requirements are met. Consult Federal
Motor Vehicle Safety Standards (FMVSS) 121 for more information.
4. Welding or altering suspension components is not permitted except where publicly stated by
Ridewell Corporation.

RAR-240 Owner’s Manual
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Configuration
1. Ride Height (also called Mounting Height) - e distance from
the bottom of the trailer frame to the centerline of the axle. Ride
height is related to frame height (the distance from the bottom of
the frame to the ground) by the following formula:
Ride Height = Frame Height - Loaded Tire Radius
e loaded tire radius for common tire sizes can be found in Chart 1.
2. Beam Centers - e centerline-to-centerline distance from one axle
seat to the other. For the RAR-240, this is also the same as the
centerline-to-centerline distance from one hanger to the other. e RAR-240 is designed to
fit up onto standard I-beam trailer frames at beam centers that correspond to standard axle
track widths as shown below with standard wheel-end equipment. Installation at wider beam
centers will reduce suspension clearances; installation at narrower beam centers will de-rate
the axle beam capacity per the axle manufacturer’s specifications. For non-standard beam
centers, frames, frame centers, axle track or wheel-end equipment, the installer is responsible
for verifying clearances, axle capacity, proper fit-up, and any additional required support structure.
Installation - General
1. See the applicable RAR-240 engineering drawing for all dimensional requirements, part numbers,
assembly details, torque values, etc. referred to in the installation procedures.
2. e exact sequence of installation and assembly of the suspension, installation of the height control
system, and completion of the axle alignment procedure is at the discretion of the trailer
manufacturer.
Chart 1
TIRE LOADED RADIUS
Trailer Width Axle Track Frame Centers Beam Centers Air Spring Centers
96” 71.5” 38” 35” 31”
102” 77.5” 44” 41” 37”
Standard Trailer Dimensions
e Ridewell model RAR-240 suspension is designed to accommodate a
range of ride heights for each specific model and can be used on a variety
of axle types for various applications. e following characteristics are
commonly referenced for set-up of the suspension:

RAR-240 Owner’s Manual
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Installation - Axle to Suspension
1. A fixture to support the axle and suspension during the welding process is recommended. Ridewell
offers weld fixture 953386.
2. Verify the beam centers and center the axle in the axle seats.
3. For drum brake axles, space the cam off the tail of the beam per the drawing and ensure that the
brake chamber brackets are oriented properly. For disc brake axles, ensure that the caliper
assemblies are oriented properly and are rotated to proper position.
4. Check the gap between the axle and the bottom of the axle seat at each end of each seat. No gap
greater than 1/16” allowed before clamping. After clamping the axle into the axle seats, no gap is
allowed.
5. Weld the axle to the suspension trailing arms per Ridewell Weld Process #1 (see page 12).
Installation - Suspension to Frame
Note: The procedure in this section is recommended by Ridewell. Minor deviations from these
guidelines are permitted, especially in the details of welding the suspension to the trailer. The
installer has ultimate responsibility for attachment of the suspension to the trailer.
1. Locate and mark the proper location of the suspension hangers and air spring plates on the trailer
frame. e frame must be clear in this area for proper suspension fit-up.
2. Frame cross members should be located as shown on the drawing.
3. Fabricate filler plates approximately as shown on the drawing and weld to the crossmembers with
¼” fillet welds (it is recommended to place welds down the length of the crossmember, not across
it) and butt weld to frames. At the hanger, a single large filler plate in place of the two small ones
may be preferable.
4. Locate and weld the hangers to the frame and filler plates with ¼” fillet welds. Stop welds
approximately ½” from corners and edges. A 1.5” diameter piece of pipe may be placed through the
holes in the hangers during this step as a stabilizer and aligning aide.
5. Weld the air spring support plate to the frame and filler plate in similar fashion with 3/16” fillet welds.
6. If required, locate a crossmember (or diagonal braces) to the front of the hangers as shown on the
drawing and attach with ¼” fillet welds.
7. All welds to be 70 ksi min. tensile strength. GMAW or FCAW recommended.
8. Assemble air springs and shock absorbers per the drawing.

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Axle Alignment
e RAR-240 suspension is equipped for simple, manual alignment of the axles. ere is 1/4” of
available adjustment at each hanger.
1. Prior to alignment, ensure all the eccentric bolt pointing arrows are at the 12 o’clock position.
See Figure 1.
2. Align the forward axle to the center of the kingpin to within ± 1/8”. See Figure 2.
3. Alignment procedure:
a. Loosen the 1.25” pivot nut and remove anti-turn washer if necessary.
b. To move the axle, turn the head of the eccentric bolt in the direction the axle is to be moved.
Maximum movement of the eccentric bolt pointing arrow from the 12 o’clock position is
to the 9 o’clock or 3 o’clock position. e eccentric bolt pointing arrow should never be
pointing below horizontal.
c. With eccentric bolts at their final setting, install anti-turn washers over the bolt heads and
weld to hangers. See Figure 3.
d. Torque the pivot nuts to 1,000 ft-lbs.
Note: Torque the pivot nuts with the suspension at ride height to prevent pre-stressing
the rubber pivot bushing.
Note: It is imperave that the pivot nuts be fully torqued prior to placing the trailer into
service. Failure to torque the pivot nuts will lead to slippage of the pivot joint,
causing rapid wear of the hanger holes and the bushing sleeve, and ulmately
leading to catastrophic failure of the suspension. A tag on the suspension and a
label in the carton of parts are provided to specify the torque of all the suspension
fasteners (see Figure 4). The label should be adhered to the trailer frame above
the suspension. Warranty coverage of the suspension is void if the pivot nuts are
not fully torqued.
e. Final check the alignment measurements and re-adjust if necessary.
4. Align the aft axle(s) to the forward axle to within ± 1/16” using the same procedure. See Figure 2.

RAR-240 Owner’s Manual
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Figure 3
Figure 1
Figure 2
NOTICE!
ECCENTRIC BOLT ARROW
MUST BE AT 12 O’CLOCK
POSITION PRIOR TO
ALIGNMENT. AFTER
ALIGNMENT INSTALL
ANT
I
I-TURN WASHER OVER
HEAD OF BOLT AND TORQUE
TO 1,OOO FT. LBS.
YOUR SUSPENSION WILL HAVE THIS
LABEL ABOVE THE ECCENTRIC BOLT
1/4 ” FILLET WELDS,
1
” LONG, AFTER AXLE
IS ALIGNED.

RAR-240 Owner’s Manual
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#1990017
MONOPIVOT 240 BOLT TORQUE
MINIMUM SPECIFICATIONS
ECCENTRIC PIVOT BOLT
SHOCK BOLT
AIR SPRING CONNECTION-3/4”
AIR SPRING CONNECTION-1/2”
1,000 FT. LBS.
160 FT. LBS.
50 FT. LBS.
25 FT. LBS.
(1,350 N•m)
(220 N•m)
(70 N•m)
(35 N•m)
After suspension has been in operation for approximately 6,000 miles
(10,000 km), all fasteners must be re-tightened to specified torque.
Repeat every 50,000 miles (80,000 km). DO NOT OVER TORQUE!
See Service Manual for Details
Torque Requirements
Figure 4
Design torque on all suspension fasteners
must be SET AND MAINTAINED BY INSTALLER.
This torque label, included in the carton of parts,
should be adhered to the chassis above the suspension.

RAR-240 Owner’s Manual
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Height Control System Installation
Bushing Check Procedure
Install the appropriate height control valve, linkages, etc. per the Extreme AirTM Height Control Valve
Installation and Operations Guide for model RAR-240.
e bushings in the RAR-240 suspension should be checked during any scheduled maintenance or any
time there is a suspected problem. Bushing problems can arise from breakdown of the natural rubber over
time or, in a severe application, by failure of the bond between the rubber and the metal inner sleeve. e
bushings should be checked if any of the following conditions are observed:
1. Uneven tire wear.
2. Abnormal forward-aft or lateral movement of the axle during operation.
3. Rapid degradation of wear washers.
4. Abnormal noises coming from the suspension.
To check, insert the flat end of a pry-bar between the sidewall of the hanger and the eye of the beam.
Applying moderate side load to the pry-bar, look for any relatively large or easy movement of the beam in
relation to the hanger. Note that a small amount of movement under load due to deflection of the rubber
is normal and acceptable. Repeat the process on the other side of the hanger. If large or easy movement is
noted, drop the beams down per the bushing replacement procedure for further inspection of the bushing
and replace if necessary.

RAR-240 Owner’s Manual
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Bushing Replacement Procedure
RAR-240 Underslung or Overslung Suspension
1. Raise and safely block up trailer and axle. Remove wheels and tires. Remove shock absorbers
from suspension.
2. Deflate air springs and, if necessary, disconnect air control valve linkage.
3. Remove pivot nuts. Remove anti-turn washers from eccentric bolt heads by grinding away
welds. Turn each eccentric bolt until arrow is pointing straight up and remove.
4. Rotate trailing arm beams down and out of hangers.
5. Inspect pivot holes and hanger surfaces for unusual wear or damage. Repair or replace
components as required.
6. Remove Huckbolt® fasteners from bushing clamp by cutting off the collar with a torch as
shown in Figure 5. Note: Huckbolt® fasteners will be replaced by conventional bolts, washers,
and nuts included in the bushing replacement kit. Remove bushing assemblies.
7. Insert new bushing assemblies into the beam eyes. Install bolts, washers, and nuts as shown
in Figures 6-7. Torque the nuts to 190 ft-lbs. minimum while making sure that the bushing
remains centered in the beam eye. Ensure bushing clamp surfaces are closed “metal-to-metal.”
Final torque nuts to 280 ft-lbs.
8. Re-assemble beams to hangers with new UHMW polyethylene wear washers placed on the
inboard sides of the beams. Note: Tanker Special suspensions have wear washers on both
inboard and outboard sides of the beams.
9. Align bushing sleeves to hanger holes and install new eccentric bolts and nuts. It is
recommended to coat the large diameter shank of the eccentric bolt with a thin layer of anti-
seize compound. Take care to not get the anti-seize compound on the threads of the bolt or
nut or under the head of the bolt.
10. Check axle alignment and re-align if necessary, per the “Axle Alignment Procedure.” Install
new anti-turn washers per Figure 3. Torque pivot nuts to 1,000 ft-lbs. with the suspension at
ride height.
11. Re-install shock absorbers.
12. Re-install wheels and tires.
13. If necessary, re-connect air control valve linkage and adjust ride height per the Extreme AirTM
Height Control Valve and Operations Guide.
Figure 5