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An Index to Service Information for 1955-56 (55th->56th Series) Packards

1955-56 (55th->56th Series) - TWIN ULTRAMATIC

SubjectApplicationDocument
Accelerator Linkage, Adjusting
throttle linkage - shift point
56th
Band Adjustments
clarification of STB 56T-6
56th
STB 56T-11 (Zones only)
Bearings, Care of Ball and Roller
installation/removal damage - proper support
(all models)
Bell Housing Oil Seal
leaks - superseded part, use of prelube
56th;
56J
Bell Housing Oil Seal
leather leaks - use neoprene
23rd-24th;
(25th-55th)
Bell Housing Oil Seal Leaks
converter mis-alignment - checks
23rd-24th;
(25th-56th)
Breather
fluid leaking - check level, relocate
56th
Bushing Tools, Service
description and illustration of use
23rd-55th
Bushings and Bearings, Service
part number reference
23rd-56th
Bushings, Service
part number reference
23rd-55th
Buzzing Noise in Reverse
pump check valve binding - rework
55th
Changes inů (Confidential)
production - with part, effective date/unit
55th
Changes inů (Confidential)
production - with part, effective date/unit
56th
Changes inů
production - with part, effective date/unit
55th
STB 55T-22 (Zones only)
Control Valve: Assemblies, Complete
identification - not interchangeable
55th-56th
Control Valve: Changes to Improve Shift Pattern
update to 56th Series - new valving kits
54th-55th
Control Valve: Torque-Tightening Controls
stuck valves - fluid/pressure leaks
(NOTE: page missing from archived document)
23rd-56th
Control Valve: Torquing Valve Body Bolts
erratic pressure readings
55th
Control Valve: Valve Springs and Spacer - Caribbean
production change - new type
5588
STB 55T-26 (Zones only)
Converter: Fluid Leaks
damaged washers - use of sealant
23rd-56th;
56J
Converter: Pump Shaft - Oil Pump Rotor Splines - see also:
Front Oil Pump
--
--
Converter: Pump Shaft - Oil Pump Rotor Splines - Worn or Stripped - Correction
new 40-spline service parts
54th-55th-56th
Converter: Pump Shaft - Oil Pump Rotor Splines - Worn or Stripped
new 40-spline service parts
54th-55th-56th
Converter: Pump Shaft and Oil Pump Rotor
worn/stripped splines - corrections, superseded parts
54th-55th-56th;
56J
Converter: Reaction Clutch Sprags
premature failure - replace in sets
54th-55th-56th;
56J
Converter: Reaction Clutch Sprags
replacement - use of reaction clutch assembly
54th-55th-56th;
56J
Converter: Reactor End Play
new measuring method and special tool
55th
Converter: Reactor End Play
revisions to checking method and special tool
56th
Converter: Reactor Shaft Bushing Clearance
direct drive failure - excessive clearance
23rd-24th;
(25th-55th)
Converter: Torque (Reactor End Play)
improved end play control, elimination of wave washer - assembly superseded, identification
56th;
56J
Converter: Torque (Reactor End Play)
wave washer kit cancelled
56th;
56J
Direct Drive Clutch: Engagement
shift valve piston and spring
55th
Direct Drive Clutch: Engagement
slipping - new high speed governor spring
55th
Direct Drive Clutch: Engagement
slipping and shift points
55th
Direct Drive Clutch: Engagement, Loss of
input/crankshaft end play, bushing position, restricted fluid passages - modifications
55th
Direct Drive Clutch: Piston Ring Installation, Converter
improper/slow engagement - check ring gap
55th-56th;
56J
Direct Drive Clutch: Slippage - Gear Start
slipping due to oil - removal of chamfers (reference for SC Vol. 29, No. 9, p. 45)
54th
Direct Shift Valve Piston Spring Seat
clutch engagement point, valve body leaks - correct installation
55th
Direct Shift Valve Piston Springs
interchangeable parts
55th
Engine Runaway - Flare - Low Brake Information
premature failure of high range clutch - summary of checks and corrections
54th-55th-56th
Engine Runaway - Low to High Shifts
high range clutch piston oil passages restricted - modification
55th
Engine Runaway - Low to High Shifts
low throttle pressure - install extension kit
55th
Engine Runaway - Low to High Shifts
low throttle pressure - install extension kit
55th
Engine Runaway
low range brake spring changes
54th-55th
Engine Runaway
new valve body separator plate, low range brake spring changes
56th
Engine Runaway/Flare - see also:
Front Oil Pump
High Range Clutch
Low Range Brake
Push Button Control
Throttle Control/Linkage
--
--
Filler Tube Length (and dipstick)
shorter - not interchangeable
55th
Fluid Temperature Affects...Upshift
loss of pressure, bushing wear - pressure tests
54th-55th-56th;
56J
Fluid, Transmission - Correction
fluid identification number
55th
Fluid, Transmission
improved type - anti-friction qualities, cold-weather perfomance
55th
Front Oil Pump - see also:
Converter Pump Shaft
--
--
Front Oil Pump and Converter Shaft Kits
new parts
54th-55th-56th
Front Oil Pump Oil Passage Restriction Test
engine runaway/flare, premature high range clutch failures - diagnosis
55th-56th
Gearshift Indicator Pointer
misalignment - new clamp
55th
High Range Clutch: (failures)
operating precautions
56th;
(54th-55th)
High Range Clutch: Burning
high range clutch spring and piston
55th-56th;
56J
High Range Clutch: Burning
spring data correction
55th-56th;
56J
High Range Clutch: Driving Plate
new heavy-duty type - installation procedure
55th-56th;
56J
High Range Clutch: Housing - Part Nos. 458950 and 6484046
clearance checks - grind welds
55th-56th;
56J
High Range Clutch: Housing - Part Nos. 458950 and 6484046
damaged seal, insufficient chamfer - return for exchange
55th-56th;
56J
High Range Clutch: Housing Identification
differentiation - check end play as installed
55th-56th;
56J
High Range Clutch: Problems
load pick up and slippage - checks, adjustments, and service precautions
55th-56th
Hydraulic Tests
preliminary service information
55th
Leaks - see also:
Bell Housing Oil Seal
Breather
Converter
Oil Loss
--
--
Linkage Adjustments - see also:
Throttle Control Rod
Throttle Linkage
Throttle Valve Lever
--
--
Low Range Brake: Cap
distorted - designed shape
56th
Low Range Brake: Functions Improperly
distorted cap
55th
Low Range Brake: Functions Improperly
distorted cap
55th
Low Range Brake: Information
harsh, noisy, runaway/flare - correct springs, new separator plate
56th
Low Range Operation
high range clutch failure - proper use of low range
23rd-25th;
(26th-56th)
Low Range Operation
high range failure - proper use
23rd-25th;
(26th-56th)
Low Regulator Valve
kickdown runaway - oil passage change
55th
Low Speed Disturbance
direct drive - alter shift point
54th-55th
Manual Valve Control Lever Inner Stop
superseded part - modified installation
55th
Oil Cooler
leaks - internal modifications, same number
55th-56th
Oil Loss
breather - relocation
(56th);
56J
Oil Loss at Breather
level, restrictions, overheating - relocation
23rd-56th;
56J
Park, Locking in
pawl and gear clearance - loose, worn, damaged parts
54th-55th-56th
Parking Lock Sticking
control lever set screw relocated - rod shortened
55th
Parking Lock Sticking
manual valve modification - new parking gear
55th
Pressure Test Plug, (Front) Pump
production change - fabricate test adapter
55th
Push Button Control: (actuator-to-manual shaft set screw)
superseded part
56th
Push Button Control: (malfunctions)
checks, adjustments, and precautions
56th
Push Button Control: Actuator Shaft (set) Screw
accessibility - new Allen head design
56th
Push Button Control: Adjusting Actuator-to-Transmission Control Valve Detent
loss/delay of high range - special procedure
56th
Push Button Control: Armature Test
special methods
56th
Push Button Control: Bent Actuator Fingers
overtravel - straightening
56th
Push Button Control: Circuit Breaker
superseded part - modification
56th
Push Button Control: Inoperative
overtravel, finger damage - rework contact segment
56th
Push Button Control: Left-Side Conversion
driver accessibility issues
56th
Push Button Control: Light Leak
at control buttons - felt mask
56th
Push Button Control: Pressure Switch
water leak/shorts - relocation
56th
Push Button Control: Push Button Type Control
preliminary information/service
56th
Push Button Control: Relay Water Trough
water leak/shorts
56th
Push Button Control: Removal of Automatic Park Relay
pawl damage
56th
Push Button Control: Removal of Control Relay
redundant part
56th
Push Button Control: Retaining Clip (Switch Actuator)
new service part
56th
Push Button Control: Supplement
Automatic Park Relay added
56th
Push Button Control: Towing Instructions
precautions
56th
Push Button Control: Towing, Road Testing and (CORRECTED)
precautions
56th
STB 56T-4C, Dealer 3
Push Button Control: Towing, Road Testing and
precautions
56th
Push Button Control: Vent
actuator - condensation and oil
56th
Push Button Control: Water in Actuator
leaks at wires
56th
Rattle (converter)
loose direct drive pressure plate screws - replace and/or retorque
55th;
(56th)
Rear Oil Pump Driver
premature wear - hardened
54th-55th-56th
Rear Oil Pump Driver
premature wear - redesigned
54th-55th-56th
Rear Oil Pump Driver
premature wear - redesigned
54th-55th-56th
Rear Oil Pump Rotor Sets
cost savings - new kits
54th-55th-56th
Selector Lever Stops
no stops - wrong lever
55th-56th
Shift Pattern
operating information
55th
Shift Pattern, Earlier
upshift modification
5640-60
Throttle Control Rod
bent - length data
24th-55th
Throttle Control Rod Adjustment
bent - rod length data
24th-55th
Throttle Control Rod Adjustment
supplemental rod length data
56th
Throttle Control Shaft Lever Extension Kit, Carburetor
unwanted kickdown - revised geometry
55th
Throttle Control Shaft Lever Extension, Carburetor
application extended to early 56th
55th-56th
Throttle Linkage Adjustment (Caribbean Carburetors)
new model information
5588
Throttle Linkage Adjustment
Training Book correction
55th
Throttle Linkage Adjustments
supplement - corrections/variations
54th-55th-56th
Throttle Linkage, Adjusting (Accelerator)
shift point
56th
Torque Specification Change
universal joint flange bolt
55th
Transmission - Caribbean
replacement - important differences
5588
Transmission Replacement - Caribbean
important differences
5588
Transmissions, Service - Stripped
shipped less bell housing
54th-55th
Universal Joint Flange Bolt
click, loosening - new type
54th-55th
Universal Joint Flange Bolt
click, loosening - new type
54th-55th

SC = Service Counselor
SL = Service Letter
STB = Service Technical Bulletin
SSB = Studebaker Service Bulletin

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Though previously published elsewhere, this work is provided with my full permission for display on the PackardInfo.com website and the personal use of visitors to that site. Any other unauthorized use, however, is expressly prohibited and may be subject to prosecution. Also, because this index was compiled from documents published by the factory, neither the author nor PackardInfo.com are responsible for errors in content arising from source information.

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