Document Xzqx6QamdvZr8ppoaVbvvQ5Vw
Roadranger
Dana Spicer Single Drive Axles
Single Reduction Axles
n
with Controlled Traction Differentials
FiT*N
One Great Drivetrain from Two Great Companies
Service Manual AXSM-0047 December 1991
For the most current information, visit the Roadranger web site at www.roadranger.com
Contents
Model Variations Description and Operation. Checking Effectiveness of Controlled Traction Differential Clutch Pack Lubrication Driver-Controlled CTD Shift Unit CTD Adjustments Shifting Seasonal CAD Fastener Tightening Specifications
All Types
Remove Differential Carrier Assembly from Axle Housing Remove Differential and Clutch Pack Assembly from Carrier
Medium-Duty CTD
Remove and Disassemble Clutch Pack Assemble and install Clutch Pack
Heavy-Duty CTD
Remove and Disassemble Clutch Pack . Assemble and install Clutch Pack
All Types
install Differential and Clutch Pack Assembly in Carrier Adjust Differential Bearing Preload Install Differential Carrier Assembly in Axle Housing Functional CTD Check (After Repair or Overhaul)
Driver-Controlled Type
CTD Shift System (Single Axles) Troubleshooting (Single Axles) CTD Shift System (Tandem Axles) Troubleshooting (Tandem Axles) Selector Valves Air Shift Unit
For Service Instructions covering other Axle Parts and Adjustments, refer to the appropriate Eaton Axle Service Manual... See back cover.
3
Adjustments
CTD Adjustments
No specific adjustments are required for the controlled traction differential unit itself. If clutch plates are worn excessively, replace clutch pack.
Shifting Seasonal ctd
Provisions are made for engaging or disengaging this type cTd with a simple manual shop adjustment.
screw
/
retainer
Procedure for Engaging and
Disengaging Seasonal CTD
Engaging -- To engage, remove the shift fork cover retainer. Push the protruding end of the shift fork away from the carrier. If the shift fork will not move, lift both wheels off the ground (leave vehicle trans mission in gear and release parking brake). While pushing on the shift fork, rotate the wheel on the shift fork side of the carrier very slowly. The shift fork should now be in the engaged position.
To reassemble cover retainer, the adjusting screw must be backed out several turns. This is done so that the shift fork cover retainer bolt holes align with the studs on the carrier. Once the shift fork cover retainer is in place (adjusting screw facing carrier), tighten the shift fork cover retainer nuts to the speci fied torque (see chart). Now turn the adjusting screw in until it contacts the shift fork. While holding the adjusting screw with a wrench, tighten the locknut to the torque specified (see chart).
Disengaging -- To disengage, remove the shift fork cover retainer. Push the protruding end of the shift fork toward the carrier. If the shift fork will not move, lift both wheels off the ground (leave vehicle trans mission in gear and release parking brake), then
push on the shift fork. The shift fork should now move to the disengaged position.
To reassemble, place the shift fork cover retainer on the carrier so that the adjusting screw is facing away from the carrier. The adjusting screw may need to be backed out of the shift fork cover retainer several turns so that the shift fork cover bolt holes align with the studs on the carrier. Once the shift fork cover is in place, tighten the shift fork cover nuts to the speci fied torque (see chart). Now turn the adjusting screw in until it contacts the shift fork. while holding the adjusting screw with a wrench tighten the locknut to the torque specified (see chart).
Fastener Tightening Specifications
Size
Ft-lbs.
N.m
Ring Gear to Support Case Bolt/Nut......................................................... . . 3/4-16 (Grade 8)
5/8-18 (Grade 8)
275-300 195-245
373-407 264-332
Shift Unit Stud/Nut.................................... . . 7/16-20 (Grade 8)
55-61
74-82
Shift Fork Cover Cap Screw................. . . 7/16-14 (Grade 5) (Permanent CTD only)
35-45
47-61
Shift Fork Cover Retainer Stud/Nut . . . 7/16-20 (Grade 8) (Seasonal CTD only)
55-61
74-82
Adjusting Screw Locknut ........................ . . 1/2-20 (Seasonal CTD only)
30-40
41-54
Other Axle Parts ......................................... . . Refer to appropriate Eaton Service Manual (See back cover)
6
CTD Overhaul w Type.)
Remove Differential Carrier Assembly from Axle Housing
IMPORTANT: Detailed procedures for each type, capacity or model axle may vary. For specific service instructions on your axle, refer to the appropriate Eaton Service Manual. The following instructions are applicable to axles equipped with Controlled Traction Differentials.
1. Driver-Controlled CTD: Remove 2. Seasonal CTD Remove nuts
shift unit nuts and flat washers. Dis and washers from shift fork cover
connect air line to permit removal retainer, then remove cover retainer.
of shift unit. Place sliding clutch
Place sliding clutch in the engaged
in the engaged position. (Sliding
position. (Sliding clutch must be
clutch must be engaged to allow engaged to allow removal of carrier
removal of carrier from housing. ) from nousing.)
3. Permanent CTD: This type CTD is always engaged. No procedure is necessary.
4. All Types CTD: Drain lubricant. Disconnect drive shaft and remove axle shafts. Remove differential carrier to axle housing cap screws and lockwashers or stud nuts. Remove differential carrier.
Remove Differential and
NOTE: If the gear set is to be reused, check tooth contact pattern and ring gear backlash before beginning disassembly. Best over haul results are obtained when used gearing is adjusted to run in established wear patterns. Omit this step if the gear set is to be replaced.
When reusing the gear set, remove the left-hand bearing cap, adjuster and lock as a unit. This will help return the gear set to its original adjustment during reassembly.
Clutch
Pack
Assembly
from
Carrier
Removing Shift Fork Shaft
Removing Sliding Clutch
1. Mount the differential carrier in a repair stand.
2. Driver-Controlled and Seasonal CTD Only: Remove shift fork seal and spring. Remove expansion plugs, then working at the lower (or small) plug hole, drive out the shift fork shaft.
WARNING: WHEN USING A DRIFT, PUNCH OR SIMILAR TOOL, WEAR SAFETY GLASSES.
3. Driver-Controlled and Seasonal CTD Only: Disengage shift fork
yoke from sliding collar. Then remove clutch and shift fork.
7
CTD Overhaul (All Types)
Remove Differential and Clutch Pack Assembly from Carrier (Cont'd)
4. If reusing gear set, punch mark bearing adjusters for reference during assembly.
5. On teeth-side of ring gear, cut lockwire and remove bearing cap
screws. Remove cap, adjuster and lock.
6. On back-side of ring gear, cut lockwire and remove bearing cap
screws. If the gear set is to be reused, remove bearing cap,
adjuster and lock as an assembly. This will facilitate correct position ing of ring gear during reassembly.
7. Remove bearing cups, then lift ring gear and differential assembly out of carrier.
Remove Drive Pinion 1. For pinion instructions, refer to appropriate Eaton Axle Service Manual covering your specific axle model. (see back cover).
8
CTD Overhaul (Medium-duty Type)
Remove and Disassemble Clutch Pack
PERMANENT CTD SHIFT FORK OPENING COVER
LOCK WASHER
1. Place differential assembly (clutch pack up) on workbench.
WARNING: TAKE PRECAUTION ARY MEASURES TO PREVENT PERSONAL INJURY OR PARTS DAMAGE DURING REMOVAL OF GEAR SUPPORT COVER (Step 2) THE COVER IS UNDER SPRING PRESSURE AND MAY POP OFF WHEN THE LAST LOCKNUT IS REMOVED.
2. Remove two self-locking nuts and bolts (180o apart) fastening support case cover, then temporar ily install two clamping bolts and nuts (see photo).
NOTE: These clamping bolts will hold cover in position while remov ing the other cover self-locking bolts and nuts.
Remove cover self-locking bolts and nuts.
EXPANSION PLUG
SHIFT FORK FOR DRIVER-CONTROLLED AND SEASONAL CTD
Removing Case Cover (with clamping nuts and bolts installed)
9
Assemble and Install Clutch Pack
NOTE: The clutch pack can be installed in differential and gear sup port case with wheel differential assembled or disassembled. With dif ferential assembled, proceed as follows:
1. All Medium-duty CTD. Place dif ferential assembly on a work bench (clutch pack mounting area up). Install ring gear on support case flange, aligning bolt holes with two temporarily-installed alignment bolts.
Remove alignment bolts.
Installing Clutch Plates Individually installing Clutch Pack and Driver
(Permanent CTD Only)
Assembly (Permanent CTD Only)
2. Install Friction Plates and Driver (Permanent ctd Only).
NOTE: Brush surface of each plate, as it is assembled, with heavy appli cation of axle lube (SAE 90).
NOTE: To assemble friction plates, one of two procedures can be used: Install driver and plates individually (Step 3) or install driver and clutch pack as an assembly (Step 4).
3. Install Friction Plates Individually (Permanent CTD Only).
a. If removed, install snap ring on friction plate driver. Then, install driver assembly (snap ring down) in bore of support case, engaging teeth of differential side gear.
b. Place one external-splined plate in ring gear bore (engaging gear internal teeth). Brush plate with lube.
c. Place one internal-splined plate on driver splines and on top of the external-splined plate. Brush plate with lube.
d. Repeat this procedure until fourteen (14) friction plates (seven internal-splined and seven externalsplned) are installed.
e. Install the last external-splined plate and pressure plate. Then in stall springs and cover (see Step 6).
4. Install Driver and Clutch Pack as an Assembly (Permanent CTD Only).
a. If removed, install snap ring on friction plate driver. Then, place driver (snap ring down) on work bench.
b. Place one external-splined plate on driver. Brush plate with lube.
c. Place one internal-splined plate on top of the external-splined plate. Brush plate with lube.
d. Repeat this procedure until fourteen (14) friction plates (seven external-splined and seven internalsplined) are installed. Then install the last external-splined plate and pressure plate.
e. Rotate external-splined plates as necessary to align the teeth. Then grasp the entire assembly by hand (see photo) and install it in the ring gear.
NOTE: As the assembly is installed, maneuver plates with external splines to align them with the ring gear teeth. Also make sure the driver engages teeth of the differ ential side gear.
f. Install compression springs and case cover (Step 6).
11
CTD Overhaul (Heavy-duty Type)
Remove and Disassemble Clutch Pack
Heavy-duty CTD Illustrated.
SIDE GEAR
BOLT
SNAP RING
DRIVER (PERMANENT CTD)
PRESSURE PLATE
CLUTCH | PACK
SNAP RING
SUPPORT CASE COVER
NUT BEARING CONE
SLIDING CLUTCH
THRUST WASHER R|NG
GEAR
PERMANENT CTD SHIFT FORK OPENING COVER
\ CAP \ SCREW
LOCK WASHER
GEAR SUPPORT
CASE
SPLINED FRICTION PLATE
TANGED FRICTION PLATE
I___ DRIVER
(DRIVER CONTROLLED AND SEASONAL CTD)
BEARING
CUP BEARING
COMPRESSION
ADJUSTER
SPRING
^.EXPANSION
PLUG
SHIFT
SHIFT FORK
FORK SHAFT
SPRING
SEAL
SEASONAL CTD SHIFT FORK RETAINER
I NUT I
DRIVER-CONTROLLED CTD SHIFT UNIT
WASHER
ADJUSTING SCREW
LOCK NUT
WASHER
NUT
EXPANSION PLUG
SHIFT FORK FOR DRIVER-CONTROLLED AND SEASONAL CTD
1. Place differential and gear support case (clutch pack up) on workbench.
WARNING: EXERCISE CARE DURING DISASSEMBLY PROCE DURE (Step 2 below). THE GEAR SUPPORT CASE COVER IS UNDER SPRING PRESSURE AND THE RING GEAR MAY FALL OFF THE SUPPORT CASE AFTER THE LAST LOCKNUT IS REMOVED. TAKE PRECAUTIONARY MEASURES TO PREVENT PER SONAL INJURY OR PARTS DAMAGE DURING PROCEDURE IN STEP 2, BELOW.
2. Remove self-locking nuts and bolts, then lift off gear support case cover and compression springs.
GEAR SUPPORT CASE COVER
COMPRESSION SPRINGS
DIFFERENTIAL AND GEAR SUPPORT CASE (FLANGED HALF)
RING GEAR
DIFFERENTIAL CASE (PLAIN HALF)
RING GEAR BOLT
Removing Gear Support Case Cover
SELF LOCKING NUT
13
Assemble and Install Clutch Pack
NOTE: The clutch pack can be installed in gear support case with wheel differential assembled or disassembled. With differential assembled, proceed as follows:
NOTE: Ring gear may fit loosely or have an interference fit on the gear support case. Proceed as necessary to assemble ring gear to support case (Step 1 or 2).
1. Install Ring Gear with interfer
ence Fit. Place gear support case assembly on bench with clutch pack side down. Position ring gear (gear teeth up) on gear support
case and align bolt holes. Tempo rarily, install two ring gear bolts to assure alignment, then tap ring
gear alternately on opposite sides with a soft-nosed hammer until gear is fully seated against gear support case flange. Turn assembly
over, then place in press (gear teeth down) on hard wood blocks. Posi tion blocks to the outside of the ring gear to allow clearance for installation of two alignment bolts.
Install alignment bolts, then pro
ceed with reassembly procedures in Step 3.
2. Install Ring Gear with Loose Fit. Place ring gear in press (gear teeth down) on hard wood blocks. Posi
tion blocks to the outside of the ring gear to allow clearance for
installation of the gear support case
assembly and two alignment bolts. Place gear support case assembly in ring gear and align bolt holes.
Install two alignment bolts in mounting holes, then proceed with
reassembly procedures in Step 3.
FRICTION
Installing Friction Plate Driver 3. Install snap ring in square ring groove of friction plate driver. Place friction plate driver (with snap ring down) in center of gear support case.
4. Place one tanged friction plate over friction plate driver, position ing tangs into slots in gear support
case (see photo). Brush top of fric tion plate with a heavy application
of axle lube (SAE 90). Place one splined friction plate over friction plate driver and brush top of this plate with lube.
5. Repeat procedures in Step 4 until there are an equal amount of friction plates of each (tanged and splined) mounted on the friction plate driver (see note below).
NOTE: Clutch pack friction plates vary with axle models (see chart on page 2 for detailed information)
Installing Friction Plates
15
CTD Overhaul (Heavy-duty Type)
Assemble and Install Clutch Pack (Contod)
(Heavy-duty CTD)
6. Place last tanged friction plate and pressure plate over friction plate driver. Then using a press and suitable adapters, compress clutch pack and install round snap ring in groove of friction plate driver.
7. If removed, press bearing cone on gear support case cover.
ALIGNMENT hoi r
Compressing Clutch Pack in a Press
COMPRESSION SPRINGS
ALIGNMENT BOLT
PRESSURE PLATE
LAt-
sum
CASE
Positioning Compression Springs on Pressure Plate
8. Place compression springs in smallest possible circle on pressure plate. Place gear support case cover over springs and temporarily install two alignment bolts. Reach through hole in gear support case cover and move compression springs radially outward as far as they will go.
Compressing Springs to Assemble Ring Gear, Case and Cover
9. Compress springs until gear case cover bottoms against gear support case. With press pressure still applied, install ring gear bolts (all bolt heads on ring gear side) and locknuts. Remove assembly from press, then tighten locknuts to correct torque (195-245 ft-lbs., 264-332 N.m).
16
CTD Overhaul a Types)
Install Drive Pinion
NOTE: If the drive pinion was removed, refer to the appropriate Eaton Service Manual covering your specific axle for instructions.
Install Differential and Clutch Pack Assembly in Carrier (ah Types ctd) n
NOTE: Lubricate bearings during the following assembly procedure:
1. Place ring gear and differential assembly in carrier Insure that ring gear and drive pinion mesh properly.
During installation, tilt carrier to allow support case pilot to rest in carrier bore, then install bearing cup as shown in photo. Also install bearing cup on opposite side of differential
2. If the same gear set is used, install the assembled bearing cap, adjuster and lock on the backface side of the ring gear. Otherwise install adjuster and cap separately.
NOTE: When installing cap, it may be necessary to tap it lightly with a hammer. Be sure cap is fully seated and threads are aligned properly. If trouble is encountered, check for cross-threading of bear ing adjuster and carrier threads.
On teeth side of ring gear, install the other adjuster and bearing cap, observing same precautions to avoid cross-threading.
3. Install and tighten bearing cap screws finger-tight. If this is diffi cult, use hand wrench.
NOTE: The assembly is now ready for adjustment of differential bear ing preload, ring gear backlash and gear tooth contact.
17
Install Differential Carrier Assembly in Axle Housing (All Types)
IMPORTANT: The following instructions cover single drive axles and tandem rear axles. For tandem forward axles (cliff. with power divider), refer to the appropriate Eaton Axle Service Manual.
IMPORTANT: Before installing carrier assembly, inspect and thor oughly clean interior of axle housing.
NOTE: Use silicone rubber gasket compound on axle housing mating surface as shown in the illustration. Compound will set in 20 minutes. Install carrier before compound sets or reapply.
1. Install differential carrier assembly in axle housing. Install stud nuts and lockwashers, tighten to correct torque.
2. Install axle shafts and stud nuts. (If used, also install lockwashers and taper dowels.)
3. Connect driveline.
4. Fill axle with correct lube to correct level.
5. Driver-Controlled CTD: Install shift unit on carrier, engaging swivel with slot in shift fork shaft. Install mounting nuts and flat washers. Torque nuts (see chart). Connect air line to unit.
6. Seasonal CTD: Position sliding clutch in the engaged or disengaged position, then install shift fork cover retainer and secure with selfIocking nuts and washers. Torque nuts (see chart).
NOTE: Shift fork cover retainer can be installed in two different posi tions; one to keep the sliding clutch engaged and the other to keep it disengaged. In the engaged position the shift fork cover retainer will have the adjusting screw facing the carrier, and away from the carrier in the disengaged position. Refer to page 6 for adjusting procedure.
Silicone Gasket Compound Pattern Differential Carrier
Mating Surface.
Torque Chart
Ft-lbs.
Shift Unit
STUD/NUT 7/16-20 (Grade 8)
55-61
Shift Fork Cover
(Permanent CTD only)
CAP SCREW
7/16-14
35-45
(Grade 5)
Shift Fork Cover Retainer
(Seasonal CTD only)
STUD/NUT
7/16-20 (Grade 8)
55-61
Adjusting Screw
(Seasonal CTD only)
LOCKNUT
1/2-20
30-40
N.m 74-82 47-61 74-82 41-54
Functional CTD Check (After Repair or Overhaul) (Single Or Tandem Axles)
NOTE: This is an operational check during or after servicing all single and tandem CTD equipped axles.
The following procedure can be
used to determine whether the CTD is shifting in and out of the engaged mode. This functional check should be performed at any time the shift system components or axle CTD components are repaired or replaced.
1. Block the vehicle wheels to pre vent rolling.
2. Place transmission in neutral and release parking brake.
3. Jack up both rear wheels of the drive axle.
4. With CTD selector valve in the disengaged position, the wheels will roll independent of one another.
5. With the CTD selector valve moved to the engaged position, the wheels will not turn independent of one another.
6. If the wheels turn independently
in Step 5, the CTD is not function ing. Proceed to check for full sys tem air pressure at shift unit.
NOTE: The unit operates at full reservoir pressure.
7. Remove shift unit and check to see if the shift unit pin and block were properly positioned into the shift fork opening.
NOTE: It is possible to install the shift unit and miss the fork open ing. If this occurs, the CTD will be locked in either the engaged or dis engaged position and will not shift. If this situation is found, reinstall the unit while carefully aligning pin into fork. Then repeat Steps 5 and 6 to verify proper function.
8. If shift unit installation and align ment was correct in Step 7, check the unit itself for proper function ing. With the shift unit removed, check it for proper travel by cycling the CTD selector valve. Travel
should be 15/16" (23.8 mm). With pin in each position, pry with a screwdriver against the pin. This pin should not move when apply ing moderate force.
9. if all of the above checks are made and found satisfactory, the failure of the CTD to properly engage involves internal axle parts.
With the shift unit removed, the CTD can be shifted in and out of engagement manually. With the shift fork away from the carrier
(engaged) the wheels should not rotate together.
19
CTD Shift System (Single Axe
CTD Shift System (Single Axles)
Description and Operation This system provides the option of operating with the Controlled Traction Differential engaged or disengaged with the use of an in-cab mounted pneumatic selector valve.
Engagement. When the selector valve lever is moved to the engaged position, the selector valve is opened and air pressure is applied to the shift unit. The shift unit is connected to a shift fork and sliding clutch. The sliding clutch moves to engaged the Controlled Traction Differential. In the engaged position, the wheel differential acts a biasing differential.
Disengagement. When the selector valve lever is moved to the disengaged position, the selector valve is closed. Air pressure in the shift unit is exhausted. The sliding clutch retracts and disengages the Con trolled Traction Differential. In the disengaged posi tion, the wheel differential functions with conven
tional differential action.
Troubleshooting (Single Axle Shift System)
IMPORTANT: Before starting a system check, operate engine until full system air pressure (reservoir pressure) is built up in the system.
CAUTION: HIGH AIR PRESSURE MAY BE PRESENT WHEN DIS CONNECTING AIR LINES DUR ING SYSTEM CHECK. EXERT CAUTION TO PREVENT POSSlBLE PERSONAL INJURY.
Check for Air Pressure and Air Leaks A simple method for quickly locat ing trouble in a shift system can be accomplished by listening for pos sible air leaks and for sound (or feel by hand) which would indicate mechanical shifting,
Check Controlled Traction
Differential System
1. Start the system check by plac ing the controlled traction selector valve in the disengaged position. Release the parking brake and place transmission in neutral.
2. Lift the wheel on the shift unit side of the axle off the ground. Turn the wheel. Both the wheel and the drive shaft should rotate. If the
wheel rotates, go to Step 6. If wheel will not rotate, proceed to the next step.
3. Verify that there is no air pres sure at the shift unit by disconnect ing the air line. If air pressure at the shift unit is present, check for pos sible exhaust port blockage at the CTD selector valve. If no blockage is found, the CTD selector valve is defective and needs replacement.
4. If there is no air pressure at the shift unit, remove the shift unit and have an assistant move the CTD selector valve back and forth. The shift unit linkage should move accordingly. If linkage does not move, disassemble shift unit and repair (see page 26). If the shift unit functions properly, proceed to Step 5.
5. With the shift unit removed, move the protruding end of the shift fork from side to side. If shift fork will not move, the problem is in the carrier assembly. Remove carrier and inspect components.
6. Have an assistant move the selector valve to the engaged posi-
tion. Turn the wheel that is off the ground. Neither the wheel or the drive shaft should rotate. If the wheel rotates, proceed to next step.
7. Verify that there is full system air pressure at the shift unit. If no air pressure is present, selector valve is defective and needs replacement.
8. If there is air pressure at shift unit, remove the shift unit by first placing the selector valve in the disengaged position. Then have an assistant move the selector valve back and forth. The shift unit link age should move accordingly. If linkage does not move, disassembly shift unit and repair (see page 26). If the shift unit functions properly, move the protruding end of the shift fork from side to side. If the shift fork will not move, remove differen tial carrier and check components.
NOTE: For CTD Functional Check, see page 19.
20
CTD Shift System (Tandem Axles)
Description and Operation
The CTD Shift System provides the option of operation with t disengaged with the use of an in-cab pneumatic valve.
Two shift units (one on each axle) engage or disengage the C valve in the system provides fast release of air pressure fr
There are two types of CTD Shift Systems for tandem axles: ( operation of the Inter-Axle Differential and both Controlled System which offers independent control of the Inter-Ax/e Di tials. These systems are illustrated on the next page.
Instruction in this manual are the same for both systems unl
he Controlled Traction Differential engaged or
ontrolled Traction Differentials. A quick release om the shift units.
1) a One-Selector Valve System controlling Traction Differentials, or (2) a Two-Selector Valve
fferential and the Controlled Traction Differei-
ess specified otherwise.
Engagement. When the selector valve lever is moved to the engaged position, the selector valve is opened
and air pressure is applied to the shift unit (or units). Each shift unit is connected to a shift fork and sliding
clutch. The sliding clutch moves to engage the Con trolled Traction Differential. In the engaged position, the wheel differential acts a biasing differential.
Disengagement. When the selector valve lever is moved to the disengaged position, the selector valve is closed. Air pressure in the shift unit (or units) is
exhausted. The sliding clutch retracts and disengag
es the Controlled Traction Differential. in the disen gaged position, the wheel differential functions with conventional differential action.
In the One-Selector Valve System, the CTD and Inter-Axle Differential are controlled by one valve and
both are engaged when the selector valve is in the engaged position.
in the One-Selector Valve System, both CTD wheel differentials and Inter-Axle Differential are disen gaged when the selector valve is in the disengaged position.
In the Two-Selector Valve System, both CTD differ entials and the Inter-Axle Differential are engaged independently.
In the Two-Selector Valve System, both CTD differ entials and the Inter-Axle Differential are disengaged independently.
CTD Shift Unit. For detailed description and operation, refer to page 25.
Inter-Axle Differential Lockout Shift Unit. For detailed description and operation, refer to the appropr
Eaton Axle Service Manual covering your axle model (see back
cover).
iate
21
CTD Shift System (Tandem Axles)
One-Selector Valve CTD Shift System
In the One-Selector Valve System, all three differentials are engaged or disengaged by a single selector valve.
Two-Selector Valve CTD Shift System
The Two-Selector Va/ve System provides independent control of both CTD Differentials and Inter Axle Differential Operation.
22
Troubleshooting (Tandem axle Shift Systems)
Except where specified otherwise, Disengage Inter-Axle Differen
the following instructions cover
tial (Two-Selector Valve System)
Controlled Traction Shift Systems with one or two selector valves.
For vehicles equipped with two selector valves, one for operating
IMPORTANT: Before starting a system check, make sure the inter axle differential is disengaged. Also, operate engine until full system air pressure (reservoir
the inter-axle differential shift unit
and the other for the CTD shift units, the following steps must be taken to make sure the inter-axle differential is disengaged.
pressure) is built up in the system. 1. Release the parking brake and
Check for Air Pressure and Air Leaks
place the vehicle transmission in neutral.
A simple method for quickly locat 2. Place the inter-axle differential
ing trouble in a shift system can be selector valve in the disengaged
accomplished by listening for pos position.
sible air leaks and for sound (or feel by hand) which would indicate
mechanical shifting.
3. Lift both wheels of the rear axle off the ground.
4. Rotate the inter-axle drive shaft.
Disengage Inter-Axle Differen If the shaft turns, the inter-axle
tial (One-Selector Valve System) differential is disengaged. If it does
For vehicles equipped with a sys not turn, the inter-axle differential
tem that engages both CTD differ shift mechanism is not functioning
entials when the inter-axle differ ential is engaged, the following
properly. Refer to the appropriate Eaton Axle Service Manual for
steps must be taken to make sure disassembly and repair.
the inter-axle differential is disen
gaged before checking the CTD shift system.
Check Controlled Traction Differential Shift System)
1. Start the system check by releas 1. Two-Valve System. Start the
ing the parking brake and place
system check by placing the CTD
transmission in neutral.
selector valve in the disengaged
2. Place the inter-axle differential selector valve in the disengaged position.
position (the inter-axle differential selector valve should still be in the
disengaged position).
3. Lift both wheels of the rear axle off the ground.
4. Rotate the inter-axle drive shaft. If drive shaft turns, the inter-axle differential is disengaged. If it does not turn, the inter-axle differential
One-Valve System. Make sure the inter-axle differential selector valve is still in the disengaged position.
Both Systems. Make sure the park ing brake is released and the trans mission is in neutral.
shift mechanism is not functioning 2. Lift the wheel on the shift unit
properly. Refer to appropriate
side of rear axle off the ground.
Eaton Axle Service Manual for
Turn the wheel. Both the wheel
disassembly and repair.
and the inter-axle drive shaft should
5. After confirming that the inter axle differential is disengaged, dis
connect the air line connected to
rotate. If the wheel rotates, go to Step 6. If wheel will not rotate, proceed to the next step.
the inter-axle differential lockout AcAUTION: HIGH PRESSURE MAY
shift unit and plug the end of the
BE PRESENT WHEN DISCON
line. NECTING AIR LINE. EXERT
CAUTION TO PREVENT POSSl-
BLE PERSONAL INJURY.
AcAUTION: HIGH PRESSURE MAY BE PRESENT WHEN DIS
CONNECTING AIR LINE. EXERT CAUTION TO PREVENT POSSlBLE PERSONAL INJURY.
3. Verify that there is no air pres
sure at the rear axle shift unit by removing the air line. If air pressure is present, check for blockage of
exhaust port at selector valve. If none is found, the CTD selector valve (or inter-axle differential
selector valve) is defective and needs replacement.
4. If no air pressure is present at the shift unit, remove the shift unit and have an assistant move the CTD selector valve back and forth. The shift unit linkage should move accordingly. If the linkage does not move, disassemble shift unit and repair (see page 26). If the shift unit functions properly, proceed to Step 5.
5. With the shift unit removed, move the protruding end of the shift fork from side to side. If the shift fork will not move, the problem is in the differential carrier assem bly. Remove carrier and inspect components.
6. Two-Valve System. Move the CTD selector valve to the engaged position.
One-Valve System. Move inter-axle differential selector valve to the engaged position.
Both Systems. Turn the wheel that is off the ground. Neither wheel or the inter-axle drive shaft should rotate.
7. If the wheel rotates, check to make sure that there is full system air pressure at the rear axle shift unit by removing the air line. If no air pressure is present, the CTD selector valve (or inter-axle differ ential selector valve) is defective and needs replacement.
8. If air pressure is present at the shift unit, remove the unit by first placing the CTD selector valve in the disengaged position. Once the shift unit is removed, have an assistant move the CTD selector valve back and forth. The shift unit linkage should move accordingly. If the linkage does not move, dis assemble the shift unit and repair (see page 26). If the shift unit functions properly, move the pro truding end of the shift fork from side to side. If the shift fork will not move, remove differential carrier and check components.
9. Use same procedure to trouble shoot forward axle controlled trac tion differential.
NOTE: For CTD Functional Check, see page 19.
23
CTD Shift System Components
Selector Valves
Controlled
Traction Differential Selector Valve
Plate
Typical Selector Valve for Driver-Controlled CTD or Inter-Axle Differential Lockout.
F^T*N
Controlled Traction Diff. Operating Instructions
Engage at any speed but never when wheels are spinning
Do not operate engaged on dry pavement Use only when additional traction is needed under adverse road conditions
CTD Instruction Plate
Inter-Axle Differential Selector Valve Plate
'E `TftAI Er.L9NI
Inter-Axle Differential
Lockout Instructions
Engage lockout only when stopped or al slow speeds and never when wheels are spinning
Do not operate lockout on dry pavement for prolonged duration Use only when additional traction IS needed under adverse road conditions
Inter-Axle Differential Lockout Instruction Plate
Inter-Axle Differential Lockout Shift Unit
For information and service instructions, refer to the appro priate Eaton Axle Service Manual (see back cover).
24
CTD Shift System Components
Air Shift Unit Replacement
Remove Unit
Disconnect air line at shift unit cover. Remove nuts, flat washers and piston air-shift unit from differ ential carrier.
NOTE: When shift unit is removed, provide container to catch oil that escapes from reservoir. Remove shift fork seal and spring.
Install Unit
1. Lubricate shift fork. Slide seal and spring assembly over fork and seal on differential carrier studs. Shift axle into Low Range.
2. Place shift unit on mounting studs and make certain shift fork actuating lever engages slot in shift fork. Install flat washers and stud nuts. Tighten nuts to 55-61 ft-lbs. (74-82 N.m).
3. When axle is installed in vehi cle, fill shift unit housing to level of filler plug with SAE 10 oil or automatic transmission fluid (see Lubrication on following page). Coat threads of filler plug with sealer and install plug.
4. Connect air lines to shift unit cover.
Air Shift Unit Overhaul
Disassemble Unit
PISTON
ACTUATING LEVER
ASSEMBLY
.COMPRESSION
> SPRING
SHIFT UNIT -HOUSING
PISTON ROO
1. Remove cap screws, lock washers, cover and gasket from housing. Drain lubricant.
2. Remove bolts, locknuts, cover at piston end of housing. Remove "O" ring.
CAUTION: DURING THE FOLLOWING PROCEDURE, THE PISTON WILL POP OUT OF HOUSING UNDER SPRING PRESSURE. EXERCISE CAUTION TO PREVENT POSSIBLE INJURY.
3. Remove locknut, flat washer, and piston from push rod. Remove "O" ring and felt oilers from piston.
COMPRESSION SPRINGS"
PISTON STOP^
4. Remove compression spring and piston stop from bore of shift unit housing. 5. Remove clevis pin, then remove push rod from shift unit housing. Remove "O" Ring from push rod.
SHIFT FORK SWIVEL
ACTUATING LEVER
Parts Inspection
Shift Fork Seal - Inspect shift fork seal for defects and tight fit on shift fork. A spring is used to assure a closer fit of seal around shift fork. If this spring is not present on axle being serviced, install one when reassembling unit.
"O" Rings, Felt Oilers and Gasket Replace "O" rings, felt oilers and cover gasket when piston airshift unit is disassembled for repair.
Compression Spring - Inspect spring for distortion, cracks, or other visual defects. Replace a faulty spring.
Actuating Lever and Pins Inspect lever pins and bearings for worn or grooved condition. Inspect actuating lever and push rod for worn or elongated holes at point where they are connected. Replace faulty parts.
Piston - Inspect piston friction surface for worn, grooved or damaged condition which will affect the piston movement in cylinder. Replace a faulty piston.
ACTUATING LEVER PIN
BEARING
6. Remove actuating lever and pin assembly from shift unit housing. Do not disassemble actuating lever.
26
Single Axle Model No. Variation
Current Production Example:
23085C
Gearing S - Single Reduction T - 2-Speed P - Planetary Double Reduction C - Single Reduction with Controlled
Traction Differential ------------ (GCW x 1000 lbs.) ----------------------- <GAWR x 1000 lbs.)
Tandem Axle Model No. Variation
Older Model Example:
23421
"E- Design Level
NOTE: Controlled Traction
Differentials can be Identified by CT before the production assembly number on the carrier,
------- Gear Diameter
----------- Gearing
1 - Single Reduction 2 - 2-Speed 3 - Planetary Double Reduction 4 - Single Reduction w/Controllf
Traction Differential
------------------ Axle Capacity (x 1000 lbs)
Current Production Example:
GAW Rating (x 1000 lbs.) Gearing S - Single Reduction T - Dual Range P - Planetary Double Reduction C - Single Reduction with Controlled
Traction Differential D - Forward Tandem Axle R - Rear Tandem Axle
Older Model No:
DS381-P*
"S" indicated single reduction and an asterisk(*) was used to identify Controlled Traction Differential.
Copyright Eaton and Dana Corporation, 2002. EATON AND DANA CORPORATION hereby grants its customers, vendors, or distributors permission to freely copy, reproduce and/or distribute this document in printed format. THIS INFORMATION IS NOT INTENDED FOR SALE OR RE SALE, AND THIS NOTICE MUST REMAIN ON ALL COPIES.
DANA
One Great Drivetrain from Two Great Companies
National Institute tor
AUTOMOTIVE
SERVICE EXCELLENCE
Roacfeanger
MORE TIME ON THE ROAD.w
The Roadranger System is an unbeatable combination of the best products from Eaton and Dana: partnering to provide you the most advanced, most trouble-free drivetrain in the industry. And it's backed by the Roadrangers: the most experienced, most expert, most accessible drivetrain consultants in the business.
For spec'ing or service assistance, call 1-800-826-HELP (4357) 24 hours a day, 7 days a week, (Mexico: 001-800-826-HELP (4357)) for more time on the road. Or visit our web site at www.roadranger.com.
AXSM-0047 12/91 POD Printed in USA