DORSEY SC20 Instruction Manual

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PARTS CATALOG & MAINTENANCE MANUAL
SC20
23.5’ CONTAINER CHASSIS
TANDEM SPRING SLIDER

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PARTS CATALOG & MAINTENANCE SCHEDULE, FIRST RELEASE
Published by PITTS ENTERPRISES, LLC.
Copyright © 2018 by Pitts Enterprises. All rights reserved. This is a copyright work and Pitts
Enterprises and it’s suppliers reserve all work in and to the work. You may not decompile, dis-
assemble, reverse engineer, reproduce, modify, or create derivative works based upon the
work without prior consent. You may use the work for your own noncommercial & personal
use. Any other use of the work is strictly prohibited.
PITTS ENTERPRISES
TELEPHONE: [phone]
FAX:
WEBSITE: WWW.PITTSENTERPRISES.NET
ADDRESS: 5734 Pittsview Hwy, Pittsview, AL 36871
DORSEY INTERMODAL
TELEPHONE: 855-4-CHASSIS
FAX:
WEBSITE: WWW.DORSEYINTERMODAL.COM
ADDRESS: 5734 Pittsview Hwy, Pittsview, AL 36871

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TABLE OF CONTENTS
GENERAL DIMENSIONS................................................................. 4
MAINTENANCE SCHEDULE .......................................................... 5
MAIN FRAME......................................................................................6
KINGPIN & UPPER COUPLER ........................................................7
SLIDER ASSEMBLY..........................................................................10
LOCKING DEVICES...........................................................................13
SUSPENSION ....................................................................................15
AXLES................................................................................................. 20
RIM & TIRE ......................................................................................... 23
TIRE INFLATION ............................................................................... 25
LANDING GEAR................................................................................ 27
BRAKE SYSTEM ................................................................................31
ELECTRICAL ..................................................................................... 36
LIGHTING ........................................................................................... 38
DECALS.............................................................................................. 39
WARRANTY........................................................................................ 40

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GENERAL DIMENSIONS

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RECOMMENDED MAINTENANCE SCHEDULE
INITIAL
PERIOD
EVERY
MONTH
EVERY
THREE
MONTHS
EVERY
FOUR
MONTHS
EVERY
SIX
MONTHS
EVERY
TWELVE
MONTHS
AT BRAKE
RE-LINE
FRAME STRUCTURE X
FRAME FASTENERS X
FRAME FASTENERS TORQUE &
CORROSION X
KINGPIN & UPPER COUPLER
X
30,000
LOCKING DEVICES X
LANDING GEAR LUBRICATION X
LANDING GEAR HARDWARE X
SUSPENSION STRUCTURE X
SUSPENSION FASTENERS
TORQUE & CORROSION 1,000 X
PIN CAGE FASTENERS TORQUE 1,000 X
HUB CAP & WHEEL SEALS X
BRAKE ADJUSTMENT & RE-
PACK WHEEL BEARINGS X
BRAKE LINING WEAR X
CAMSHAFT COMPONENTS &
LUBRICATION X
BRAKE ADJUSTER & CLEVISES
LUBRICATION X
BRAKE DRUM X
WHEEL END COMPONENTS
X
100,000
BRAKE CHAMBERS & SLACK
ADJUSTERS X
100,000
LUG NUTS & HUB CAP NUTS 50-100 X
BRAKE CHAMBER PUSH ROD X
AIR BRAKE SYSTEM X
ELECTRICAL SYSTEM X

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MAIN FRAME ASSEMBLY
VISUAL INSPECTION
BEFORE EACH OPERATION
PERIODIC INSPECTION
EVERY THREE MONTHS
• MISSING COMPONENTS
• FASTERNERS
• CRACKED WELDS
• CRACKED METAL
• DISTORTED COMPONENTS
• LOCKING DEVICES FUNCTIONING PROPERLY
• SLIDER LOCK PIN S FUNCTIONING PROPERLY
• LARGE ARES OF MISSING PAINT
• ADNORMAL WEAR
WARNING
DAMAGED PARTS, CRACKED WELDS, OR ADNORMAL WEAR MAY
RESULT IN PROPERTY DAMAGE, SERIOUS INJURY, OR DEATH.

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KINGPIN & UPPER COUPLER ASSEMBLY
VISUAL INSPECTION
BEFORE EACH OPERATION
• CRACKED WELDS
• CRACKED METAL
• DISTORTED COMPONENTS
• LARGE ARES OF MISSING PAINT
• ADNORMAL WEAR
PERIODIC INSPECTION
EVERY THREE MONTHS OR
30,000 MILES
• USING A 48 INCH STRAIGHT EGDE, CHECK THE FLATNESS IN ALL
DIRECTIONS. ANY BUMPS, VALLEYS OR WARPING WILL CAUSE
UNEVEN LOADING OF THE FIFTH WHEEL, WHICH COULD RESULT
IN DAMAGE TO THE TOP PLATE & POOR LOCK LIFE. REPLACE THE
CHASSIS UPPER COUPLER PLATE IF FLATNESS EXCEEDS THE
SPECIFICATIONS SHOWN BELOW.
WARNING
DAMAGED PARTS, CRACKED WELDS, OR ADNORMAL WEAR MAY
RESULT IN PROPERTY DAMAGE, SERIOUS INJURY, OR DEATH.

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KINGPIN
VISUAL INSPECTION
BEFORE EACH OPERATION
• CRACKED WELDS
• CRACKED METAL
• DISTORTED COMPONENTS
• ADNORMAL WEAR
• NICKS
• GOUGES
PERIODIC INSPECTION
EVERY THREE MONTHS OR
30,000 MILES
• USING A KINGPIN GAUGE CHECK THE KINGPIN LENGTH.
• USING A KINGPIN GAUGE CHECK THE WEAR ON BOTH THE 2
INCH AND 2.88 INCH DIAMETERS. REPLACE THE KINGPIN IF THE
APPROPRIATE DIAMETERS ENTERS THE GAGE SLOT.
WARNING
DAMAGED PARTS, CRACKED WELDS, OR ADNORMAL WEAR MAY
RESULT IN PROPERTY DAMAGE, SERIOUS INJURY, OR DEATH.

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MAIN FRAME & UPPER COUPLER
COMPONENTS
KINGPIN
FRIDINGEN
141125303
UPPER COUPLER PLATE
DORESY INTERMODAL
17-PRT-AP475
LANDING GEAR BRACKET
DORESY INTERMODAL
17-PRT-AP462
LANDING GEAR REINFORCEMENT
DORESY INTERMODAL
CURBSIDE: 17-PRT-AP463
ROADSIDE:: 17-PRT-AP464
LANDING GEAR CROSS BRACE
DORESY INTERMODAL
17-PRT-AP013
LANDING GEAR CLIP
DORESY INTERMODAL
17-PRT-AN042
GLADHAND PLATE
DORESY INTERMODAL
17-PRT-AP456
TRIP ANGLE
DORESY INTERMODAL
17-PRT-AP465
SLIDER WEAR PLATE
DORESY INTERMODAL
17-PRT-AP467

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SLIDER ASSEMBLY
VISUAL INSPECTION
BEFORE EACH OPERATION
PERIODIC INSPECTION
EVERY THREE MONTHS
• MISSING COMPONENTS
• FASTERNERS
• CRACKED WELDS
• CRACKED METAL
• DISTORTED COMPONENTS
• LARGE ARES OF MISSING PAINT
• ADNORMAL WEAR
WARNING
DAMAGED PARTS, CRACKED WELDS, OR ADNORMAL WEAR MAY
RESULT IN PROPERTY DAMAGE, SERIOUS INJURY, OR DEATH.

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PIN CAGE ASSEMBLY
VISUAL INSPECTION
BEFORE EACH OPERATION
• MISSING COMPONENTS
• FASTERNERS
• CRACKED WELDS
• CRACKED METAL
• DISTORTED COMPONENTS
• VERIFY LOCKING PINS FULLY EXTEND & PASS THROUGH THE
LOCKING HOLES IN THE MAIN FRAME
• ADNORMAL WEAR
• REMOVE ANY DEBRIS BETWEEN THE PIN CAGE & MAIN FRAME
ASSEMBLY
PERIODIC INSPECTION
FIRST 1,000 MILES
&
EVERY FOUR MONTHS
• CHECK PIN CAGE & MOUNTING PLATE AT THE FRONT OF THE
SLIDER ASSEMBLY FOR DAMAGE.
• CHECK MOUNTING FASTENERS TORQUE. TORQUE = 135-150 ft-lb
• CHECK LOCKING PINS, LINKS, ROD, & SPRINGS FOR WEAR OR
DISTORTION
WARNING
DAMAGED PARTS, CRACKED WELDS, OR ADNORMAL WEAR MAY
RESULT IN PROPERTY DAMAGE, SERIOUS INJURY, OR DEATH.

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SLIDER ASSEMBLY
COMPONETS
PIN CAGE
HUTCHENS
17-PRT-AH986
TAIL LIGHT BAR
DORSEY INTERMODAL
CURBSIDE: 17-SUB-AH058
ROADSIDE: 17-SUB-AH059
MUD FLAP BRACKET
DORSEY INTERMODAL
17-PRT-AP509
LICENSE PLATE MOUNT
DORSEY INTERMODAL
17-PRT-AP503
AIR TANK BRACKET
DORSEY INTERMODAL
17-PRT-AP511
BUMPER ASSEMBLY
DORSEY INTERMODAL
17-SUB-AH060
TUBE: 17-PRT-AH987
SLIDER WEAR PAD
HUTCHENS
17-PRT-AP514
WEAR PAD SCREW
HUTCHENS
17-PRT-AJ467
INNER GUIDE
DORSEY INTERMODAL
17-PRT-AP498

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LOCKING DEVICES
VISUAL INSPECTION
BEFORE EACH OPERATION
• MISSING COMPONENTS
• FASTERNERS
• CRACKED WELDS
• CRACK METAL
• ENSURE TWIST LOCKS ARE RETAINED IN WORKING POSITION
& LOCK PROPERLY
PERIODIC INSPECTION
ANNUALLY
• LUBRICATE TWIST LOCKS & ENSURE SMOOTH OPERATION
WARNING
DAMAGED PARTS, CRACKED WELDS, OR ADNORMAL WEAR MAY
RESULT IN PROPERTY DAMAGE, SERIOUS INJURY, OR DEATH.

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LOCKING DEVICE
COMPONENTS
TWIST LOCK—RH
BUFFERS OR TOCA
17-PRT-AF412
TWIST LOCK—LH
BUFFERS OR TOCA
17-PRT-AF413
SAFETY LATCH—RH
BUFFERS OR TOCA
17-PRT-AF598
SAFETY LATCH—LH
BUFFERS OR TOCA
17-PRT-AF599

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SUSPENSION
VISUAL INSPECTION
BEFORE EACH OPERATION
• MISSING COMPONENTS
• BUSHINGS WEAR
• FASTERNERS
• CRACKED WELDS
• CRACKED METAL
• BROKE OR CRACKED LEAF SPRINGS
INITIAL BREAK IN PERIOD
FIRST 1,000 MILES
• ALL FASTENERS SHOULD BE CHECKED TO ENSURE THAT
RECOMMENDED TORQUE VALUES ARE BEING MAINTAINED.
PERIODIC INSPECTION
EVERY FOUR MONTHS OR
25,000 MILES
• ALL FASTENERS SHOULD BE CHECKED TO ENSURE THAT
RECOMMENDED TORQUE VALUES ARE BEING MAINTAINED.
WARNING
DAMAGED PARTS, CRACKED WELDS, OR ADNORMAL WEAR MAY
RESULT IN PROPERTY DAMAGE, SERIOUS INJURY, OR DEATH.
DO NOT WELD LEAF SPRING.
DO NOT OPERATE WITH CRACKED OR BROKEN SPRING.

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SUSPENSION
AXLE SEATS & BOTTOM PLATE WELDING INSTRUCTIONS

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SUSPENSION
TORQUE VALUES
ITEM NO FASTENER TORQUE
OILED
11 1/8”-12—EQUALIZER NUT 590 ft-lb
21”-14—RADIUS ROD NUT 540 ft-lb
37/8”-14—U-BOLT ASSEMBLY 350 ft-lb
45/8”-18—RADIUS ROD CLAMP NUT 130 ft-lb
55/8”-18—SPRING RETAINER NUT 35 ft-lb
1. FOR CONSISTENT CLAMP LOADS, LUBRICATE ALL FASTENERS &
TORQUE TO OILED SPECIFICATIONS PER THE AXN TORQUE DECAL
(AX-MS-TD-06-14).
2. U-BOLT NUTS MUST BE TIGHTENED IN ALTERNATING PATTERN.
3. AXN TORQUE DECAL (AX-MS-TD-06-14) SHOULD BE APPLIED ON
THE ROADSIDE OF THE TRAILER IN CLEAR VIEW, ABOVE THE IN-
STALLED SUSPENSION.
4. AFTER INITIAL BREAK IN PERIOD, CHECK FASTENERS TO ENSURE
PROPERLY MAINTAINED TORQUE. U-BOLT
TIGHTENING
PATTERN

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SUSPENSION
ALIGNMENT
1. BEFORE TAKING AXLE ALIGNMENT MEASUREMENTS, MAKE
SURE THE TRAILER IS UNLOADED AND FREE THE SUSPENSION
OF ANY “BINDS” BY PUSHING THE TRAILER BACKWARD & THEN
PULLING THE TRAILER FORWARD. WHILE PULLING THE TRAILER
FORWARD ON A LEVEL FLOOR, APPLY THE BRAKES & RELEASE.
THIS WILL ASSURE THAT AN ADJUSTABLE UNDERCARRIAFE IS
IN ITS REARMOST LOCKED POSITION. THE TRAILER MUST BE
LEVEL FROM SIDE TO SIDE AS WELL AS FROM FRONT TO REAR.
2. USE AXLE END EXTENDERS OR REMOVE THE OUTER WHEELS
AND ANYTHING ELSE THAT MAY BE IN THE OF THE MEASURING
TAPE TO ACHIEVE A STRAIGHT LINE FROM THE KINGPIN TO THE
AXLE ENDS.
3. MEASURE DISTANCES A & B FROM THEKINGPIN TO FRONT AXLE.
THESE MUST BE WITHIN 1/8 INCH OF EACH OTHER. MEASURE
DISTANCES C & D BETWEEN AXLES. NOTE THAT ALL CURRENT
AVAILABLE TRAILER AXLES HAVE DIMPLES OR RECESSES AT
THE CENTER OF THE AXLE SPINDLE. THESE ALSO MUST BE
EQUAL WITHIN 1/16 INCH OF EACH OTHER. DETERMINE LATERAL
CENTERLINE OF TRAILER BODY & AXLES. DISTANCE E SHOULD
NOT EXCEED 1/4 INCH FOR EITHER AXLE.
REFER TO TTMA RP NO. 71-15 FOR MORE DETAILS.
CAUTION
ALWAYS MEASURE TO THE FRONT AXLE ENDS FOR ACCURATE
ALIGNMENT.
AVOID MEASURING TO RIMS, SUSPENSION BRACKETS, HUB CAP
VENT HOLES, BRAKE DRUMS AND THE LIKE. THIS CAN RESULT IN
IMPROPER ALIGNMENT.
IF DIFFICULTY IS ENCOUNTERED IN OBTAINING TRUE ALIGNMENT,
CHECK & REPAIR OR REPLACE PROBLEM SUSPENSION PARTS.
ALWAYS ALIGN ANY SUCCEEDING AXLES WITH THE FRONT AXLE,
NOT THE KINGPIN.

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SUSPENSION COMPONENTS
ITEM
NO PART NUMBER DESCRIPTION
1FH66-0100 FRONT HANGER
2FH66-0200 MIDDLE HANGER
3FH66-0300 REAR HANGER
4FH66-0504/350 ADJ. RADIUS ROD
5FH66-0515/480 FIXED RADIUS ROD
6FH66-0509 U BOLT
7FH66-0506 SPRING SEAT
ITEM
NO PART NUMBER DESCRIPTION
817-PRT-AJ756 LEAF SPRING—LOW
ARCH
9FH66-0507 AXLE SEAT
10 FH66-0508 SPRING CLAMP PLATE
11 FH66-0510 U BOLT NUT
12 FH66-0514 RADIUS ROD BOLT
13 FH66-0520 RADIUS ROD NUT

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AXLES
AFTER FIRST 3,000 MILES
OR
AFTER FIRST MONTH
EVERY 10,000 MILES
OR
EVERY MONTH
EVERY 50,000 MILES
OR
EVERY SIX MONTHS
EVERY 100,000 MILES
OR
EVERY TWELVE MONTHS
CHECK BRAKE LININGS FOR
WEAR XX
CHECK BRAKE LINING TO
DRUM CLEARANCE XX
CHECK S-CAMSHAFT FOR
PROPER OPERATION XX
LUBRICATE S-CAMSHAFT
BEARING BUSHINGS XX
CHECK SLACK ADJUSTERS
FOR CORRECT FUNCTION XX
CHECK AIR BRAKE SYSTEM
FOR LEAKS XX
CHECK SERVICE & PARKING
BRAKE PERFORMANCE XX
CHECK AXLE COMPONENTS
FOR CRACKS OR DAMAGE XX
CHECK HUB LUBRICATION
LEVEL OR EXCESSIVE
LEAKAGE
XX
PACK HUB BEARINGS WITH
FRESH LUBRICANT X
CHECK WHEEL BEARING
END PLAY XX
CHECK TORQUE OF ALL
NUTS & BOLTS XX