tc-270 transfer case parts & service manual
Contents
1. 7 14000 eee aaa wawa aaa aaa nana akara aaa 5 2 Disassembly of the Upper Input aaa aa aaa aaa wana aaa 5 3 Disassembly of the Intermediate 5 4 Disassembly of the Rear Output 4 2 1 5 5 Disassembly of the Front Output Shaft and 5 6 ASSEMBLY 6 0 Assembly Of O Ep 6 1 Assembly of the Upper Input 6 2 Assembly of the Intermediate aaa zana 6 3 Assembly of the Rear Output 6 4 Assembly of the Front Output Shaft and 6 5 General ASSEMBIY 6 6 Assembly 01 2116 Oil PUMP 6 7 TORQUE SPECIFICATIONS 7 0 ILLUSTRATED PARTS AND LIST 8 0 TOOLS 9 0 Copyright 1996 Fabco Automotive Corporation 151 Lawrence Drive Oakland CA 94551 1 0 270 TRANSFER CASE 1 1 INTRODUCTION The Fabco TC 270 two speed transfer case is designed for use in all wheel drive vehicles The transfer case provides drive to2. FRONT DRIVE ENGAGEMENT NDICATOR SWITCH 144 NOT APPLY AR amp NPT APPLY FOR UNDERDRIVE AR FOR FRONT SPRING RETURN TO DRIVE ENGAGEMENT DIRECT DRIVE SPRING RETURN RET 10 DISENGAGEMENT FRONT VIEW FABCO TC 270 TRANSFER CASE SEC 1 3 P1 EXTENDED INPUT SHAFT FOR PTO OPTION T DECLUTCH SHIFT DETAILS FRONT SECTIONAL VIEW TC 270 TRANSFER CASE SEC 1 3 P2 1 4 NPT FOR OIL DRAIN REAR VIEW 270 TRANSFER CASE SEC 1 3 P3 2 0 LUBRICATION 2 3 INSPECTION 2 1 RECOMMENDED LUBRICANTS The oil is to be maintained at the level of the On Highway Vehicles fill plug at all times Check at the following intervals 1 Heavy Duty Engine Oil Highway Service 1 000 Miles Temperature Grade Off Highway Service 40 Hours Above 10 F SAE 50 With every oil change the shift cylinder air lines and valves should be inspected for leaks and Below 10 F SAE 30 possible malfunctioning Low pressure conditions can cause partial clutch Be sure to specify heavy duty type engagement which may result in premature meeting MIL L 2104B specifications wear or damage 2 Mineral Gear Oil 2 4 OIL CHANGE Temperature Grade The transfer
3. AUTOMOTIVE CORPORATION TC 270 TRANSFER CASE SERVICE MANUAL Fabco Automotive Corporation Livermore Ph 925 454 9500 1 800 967 8838 FAX 925 454 9501 www fabcoautomotive com TABLE OF CONTENTS SECTION TC 270 TRANSFER CASE SERVICE MANUAL 1 0 Introduction 11 1 2 Assembly ag aia 1 3 LUBRICATION 2 0 Recommended Lubricants aaa wana ooo aaa 2 1 Off Highway and Mining 2 2 IIS 2 3 Oil CHANGE 2 4 Draining the 2 5 Refilling the Qil 2 6 Operating 41075 2 7 CLEANING INSPECTION 3 0 Cleaning izy aa 3 1 Drying amp Corrosion 3 2 3 3 GENERAL INSTRUCTIONS 4 0 4 1 Assembly Precaution Swiss srities a 4 2 8 Installation 4 3 DISASSEMBLY 5 0 General a Oi A A a A oi na da i de 5 1 Disassembly of
4. 91 30 Install a new gasket If removed install a new seal into the input carrier Install the input carrier assembly onto the transfer case Install and torque to specifications the input carrier hardware See Fig 91 A CAUTION THE WORD ON THE CARRIER MUST LINE UP WITH THE TOP OF THE TRANSFER CASE HOUSING FAILURE TO DO SO WILL RESULT IN LUBRICATION BLOCKAGE TO THE UPPER INPUT SHAFT Fig 92 31 Install the input shaft yoke Using a dial indicator and gently prying upwards the input shaft yoke check that the end float is 0 003 0 008 loose Torque to specification See Fig 92 NOTE IF THE END FLOAT IS NOT WITHIN SPECIFICATION 0 003 0 008 loose THE SHIM PACK SHOULD BE REMOVED AND REPLACED WITH A SHIM COMBINATION WHICH WILL PROVIDE THE PROPER END FLOAT 32 Install the sensor pin the shift indicator light switch and two 2 copper washers into the declutch housing The rounded end of the sensor pin must face inward Check for continuity across the leads of the sensor with a continuity tester The tester should indicate a closed circuit condition with air pressure applied to the air shift cylinder See Figs 93 94 Fig 95 33 Using a new gasket secure the declutch housing cover plate with four 4 1 4 20 bolts Torque to specification See Fig 95 Fig 96 34 Using a new o ring insert the adapter tube for the high low shift cylinder into the transfer case See Fig
5. 96 Fig 97 35 Install the piston stop rings high low shift spring and the high low shift piston with a new o ring on the end of the high low shifter shaft Compress the spring with the piston and secure with a 1 2 13 lock nut See Fig 97 Fig 98 36 Install a new oil soaked felt wiper onto the piston assembly Install the cylinder housing over the piston assembly See Fig 98 WARNING WHEN INSTALLING THE CYLINDER OVER THE PISTON ASSEMBLY EXCERCISE CAUTION NOT TO NICK THE O RINGS OR TO DISTORT THE FELT WIPER FAILURE TO DO SO COULD RESULT IN A LEAKING HIGH LOW SHIFT CYLINDER Fig 99 37 If equipped with neutral Install the outer half of the shift cylinder onto the high low shift cylinder Secure the assembly with four 4 1 4 20 studs and nuts Torque to specification See Fig 99 Fig 100 38 Insert a 7 16 Allen wrench into the adjustment hole on the opposite end of the high low shift shaft Turn the shaft until the sliding clutch gear bottoms out or touches the bearing cone inside the lower direct drive gear Back off one 1 complete turn to set the adjustment See Fig 100 Fig 103 Fig 101 40 Safety lock the lock nut by bending the tabs of 39 Tighten the lock nut against the high low shift the steel locking plate over the flats of the nut and fork See Fig 707 the shift fork See Figs 102 103 7 Fig 104 41 Using a new gasket secure both the s
6. compressed air for any dirt removal Use only approved high efficiency vacuum cleaners suitable for use with asbestos not dry brush deposits accumulations of dirt from components What cannot be removed with the high efficiency vacuum cleaner should be washed with a water soaked rag The rag should not be wrung dry but should be disposed of together with other wastes containing asbestos in specially sealed and marked containers in accordance with EPA and OSHA regulations 5 Do not wear protective clothing away from the working area vacuum clean clothing before removal Shower if possible before going home These suggestions are neither complete nor authoritative on the subject of working with asbestos but are meant as a warning of possible risk is the responsibility of the supervising authority to be aware of the possible dangers involved and to provide suitable training precaution and protection for those working in an asbestos environment 5 0 DISASSEMBLY Disassembly and assembly of the Fabco TC 270 transfer case is a relatively simple procedure which can made easier by the use of some very simple tooling Details of all tooling are given in the tooling section for manufacture in your own facilities or Fabco Automotive may be contacted for a price and availability 5 1 GENERAL DISASSEMBLY 1 After removing the transfer case from the 4 If so equipped remove the lubrication lines and vehicle thoroughly clean the
7. exterior filter Note the location and routing of the lines so that they may be correctly reinstalled 2 Remove the drain plug and drain the oil See Fig 2 Fig 3 Fig 1 5 If so equipped remove the oil pump cap shims spacer ring oil pump cartridge assembly and 3 Mount the transfer case in a suitable fixture pressure relief spring On all other models remove The fixture should be such that the transfer case the blanking cover See Fig 3 can be rotated so that either the front or the rear of the case is facing upward A transfer case mounted in a typical fixture is shown in Fig 1 Fig 4 6 If so equipped remove oil strainer See Fig 4 Fig 7 9 Remove the air shift cylinder and neutral which is shown if so equipped located on the front side of the transfer case See Fig 7 Fig 5 7 Remove the shift shaft access cover plate and shift cylinder bore cap See Fig 5 Fig 8 10 Gently rock the cylinder to and fro to aid in removing the bottom portion of the air shift cylinder See Fig 8 Fig 6 8 Remove the rear output yoke See Fig 6 Fig 9 11 Bend straight the tabs of the lock plate on the shifter shaft assembly inside the transfer case Using a 9 16 Allen wrench inserted into the shift cylinder bore and an open end wrench loosen the adjustment nut on the shifter shaft assembly See Fig 9 Fig 10 12 Remove the front drive engagement indicator swi
8. from the front output shaft carrier and discard PRESS Fig 40 3 Place the shaft assembly in a press such that the rear face of the bearing is supported by the separator and the press arbor is against the threaded end of the shaft See Fig 40 4 Press the shaft through the carrier bearings and spacer 5 Remove the bearing cups from the carrier only if necessary THIS CONCLUDES THE DISASSEMBLY OF THE FRONT OUTPUT SHAFT AND CARRIER 6 0 ASSEMBLY Make sure all parts are clean dry and lint free Any traces of storage wax or paper should be removed Leave bearings and cups in their wrappers until ready to use Do not handle parts any more than necessary Unless indicated otherwise part mating surfaces should be given a light coating of lubricant Lubriplate is an acceptable grease A substitute may be used using a mixture of chassis grease and 30W engine oil The mix should be thin enough to apply with a small brush 6 1 ASSEMBLY OF SUBASSEMBLIES In the following assembly procedures it is assumed that the various shaft assemblies were completely disassembled Skip any step that refers to a part that is already assembled Refer to section 4 2 in this manual for assembly precautions 6 2 ASSEMBLY OF THE UPPER INPUT SHAFT 1 If removed during disassembly install a new oil seal and bearing cup in the upper input shaft carrier If removed install a new key in the input shaft Fig 41 2 Heat and
9. joint yoke or companion flanges should be removed with emery cloth and should also be coated with Lubriplate or the equivalent on the seal operating area prior to installation 8 ln many of the procedures when a part is assembled with a press fit it is recommended that the part be heated prior to installation The part should be placed in an oven and heated to no more than 300 F Excessive heat may change the metallurgical properties of the part Heated components should be allowed to cool to room temperature before end float measurements are made CAUTION ALTHOUGH DOES RECOMMEND ITS USE IN TRANSFER CASES IF FORMED IN PLACE GASKET IS USED FOR REPAIRS EXTREME CAUTION MUST BE EXERCISED TO PREVENT THE COMPOUND FROM ENTERING BEARINGS OIL GALLERIES PASSAGES OR TAPPED HOLES ALL BEADS MUST BE KEPT SMALLER THAN 1 8 INCH DIAMETER 4 3 REMOVAL 8 INSTALLATION 4 3 1 REMOVAL Remove fill and lower drain plugs and drain gear lubricant Disconnect wires leading to indicator light switch and temperature sensor if used Disconnect and tag shift cylinder air lines Disconnect speedometer cable Disconnect drivelines at flanges or yokes If the transfer case is equipped with a PTO mounted hydraulic pump remove four capscrews and slide pump out of PTO Secure the pump to the frame to avoid damage to hydraulic lines The pump should be secured in a position that will not hinder the removal of the tr
10. sealing face of the rear carrier Using two 2 110 to 140 7 Shims 5 16 18 x 1 1 2 long bolts secure the spacer ring 141 and Greater Consult Fabco Engineering assembly to the rear carrier See Fig 110 CAUTION TO AVOID DAMAGE TO THE SEALING SURFACE OF THE SPACER RING ASSEMBLY TIGHTEN THESE BOLTS FINGER TIGHT ONLY Fig 112 5 After shim measurements are taken and noted remove the spacer ring and pump cartridge assembly from the end of the intermediate shaft Install the pressure relief spring into the cavity at the end of the intermediate shaft See Fig 112 Fig 113 Fig 114 6 Liberally grease all of the components of the pump cartridge assembly and reinstall Seat the pressure relief spring by pushing down on it several times See Figs 113 114 Fig 115 7 Reinstall the spacer ring assembly with the bushing and gasket onto the end of the intermediate shaft See Fig 115 CAUTION THE CARTRIDGE MUST MATE WITH THE SLOT ON THE INTERMEDIATE SHAFT SEE FIG 109 NOTE THE OIL GROOVE OF THE SPACER RING ASSEMBLY BRONZE BUSHING MUST BE IN THE 6 O CLOCK POSITION THIS POSITION FACES THE BOTTOM OF THE TRANSFER CASE 8 Place the number of shims determined from steps 3 4 on top of the spacer ring Fig 116 9 Install the oil pump cap onto the spacer ring and pump cartridge assembly See Fig 116 ZA CAUTION THE PIN IN THE OIL PUMP CAP MUST BE POSITIONED SU
11. sliding clutch gear groove If this is not met the air shift cylinder must be disassembled and an additional plastic washer 0 030 thick must be installed See Fig 86 CAUTION DO REACH INTO THE DECLUTCH HOUSING WHEN APPLYING AIR PRESSURE TO THE DECLUTCH SHIFT CYLINDER Fig 87 26 With air pressure still applied install a new gasket onto the declutch housing Install the front output shaft and carrier assembly Torque the attachment hardware to specification See Fig 87 NOTE THE OIL DRAIN CAVITY ON THE CARRIER MUST BE IN THE 6 O CLOCK BOTTOM POSITION THE OIL FITTING IS IN THE 10 O CLOCK POSITION Refer to Fig 107 27 If removed install a bearing cup into the transfer case housing upper rear bore Fig 88 Fig 89 28 Place the stack of shims removed during disassembly on the rear input shaft bore of the transfer case housing Install the top rear cap noting the alignment of the oil grooves in the cap with the oil gallery holes in the transfer case housing Tighten but do not torque the cap bolts at this time See Figs 88 89 WARNING FAILURE PROPERLY ALIGN THE CAP WITH THE TRANSFER CASE COULD LEAD TO LUBRICATION BLOCKAGE OF THE UPPER INPUT SHAFT Fig 90 29 the transfer case over Install the front input shaft assembly threaded end up into the transfer case housing See Fig 90 Fig
12. 3 3 Install the intermediate underdrive gear and bearing cone onto the intermediate shaft end with the hole See Fig 43 THIS CONCLUDES THE ASSEMBLY OF THE INTERMEDIATE SHAFT 6 4 ASSEMBLY OF THE REAR OUTPUT SHAFT 1 Place the rear output shaft with the fine threaded end in an upright position protecting the shaft threads and splines Fig 46 Fig 45 3 If removed during disassembly press the 2 Using a wooden block to hold the shaft in an bearing cups into the lower direct drive gear See upright position install 116 clutch collar gear onto Fig 46 the shaft See Fig 45 4 the bearing cones in an oven CAUTION WHEN PART IS ASSEMBLED WITH A PRESS FIT IT IS RECOMMENDED THAT THE PART BE HEATED PRIOR TO INSTALLATION IN A SUITABLE OVEN AT A TEMPERATURE NO GREATER THAN 300 HEATED COMPONENTS MUST BE ALLOWED TO COOL BEFORE END FLOAT MEASUREMENTS ARE MADE 5 Install the inner bearing cone bearing spacer ring lower direct drive gear and outer bearing cone with bearing cups onto the shaft 6 To set the lower direct drive gear end float use special tool 866 749 and place over the shaft Tighten the spanner nut down using special tool 866 687 006 7 Attach a dial indicator as shown and record the gear float by lifting up on the lower direct drive gear The gear float should be 0 0005 0 0020 loose See Fig 47 8 If gear end float is not within spe
13. CH THAT IT CONTACTS THE CUTOUT GROOVE OF THE PUMP CARTRIDGE ASSEMBLY FAILURE TO DO SO WILL CAUSE THE PUMP NOT TO OPERATE 10 Apply Permatex 2 or the equivalent to the mounting bolts and evenly torque according to specifications THIS CONCLUDES THE ASSEMBLY OF THE OIL PUMP SHOWN 45 LB FT OIL LEVEL amp DRAIN PLUG 50 LB FT TEMPERATURE SENSOR 251 OIL FILTER BRACKET 15 LB FT SSSASAA a a FRONT DECLUTCH SHIFT DETAILS 45 LB FT Z 22242 im O OPTIONAL NS 2 rg 20385 500 LB FT 2 ESAs nix 0 a 7 L 70 LB FT 15 LB FT SEE ABOVE FOR SHIFTER DETAILS 600 LB FT SW 44722 2 AL i 600 LB FT Hora 9 45 LB FT y 7 LB FT N M s zo 00272 600 LB FT 7 LB FT 25 LB FT 250 LB FT R M H sS ME OPTIONAL NEUTRAL HIGH LOW SHIFT ASSEMBLY R I 25 LB FT 60 LB FT ALL TORQUE VALUES ARE FOR DRY UNLUBRICATED THREADS AND SHOULD BE WITHIN 10 OF THE VALUES SHOWN 3 99 SECTION 7 0 TC 270 TORQUE SPECIFICATIONS 9 0 TOOLS Details of tooling to facilitate servicing of Fabco TC 270 Transfer Case Service tools may be manufactured to these drawings or Fabco Automotive may be contacted for price and availability The manufacture of these tools should be carried out by professional machinists and certified
14. CLUTCH HOUSING ATTACHED TO THE TRANSFER CASE Fig 21 21 Remove the yoke from the upper input shaft See Fig 21 Fig 22 22 Remove the ten 10 bolts securing the seal and bearing carrier of the upper input shaft See Fig 22 Fig 23 23 Screw two 2 7 16 14 NC bolts into the carrier to aid in lifting it from the transfer case housing See Fig 23 CAUTION DO USE SCREW DRIVERS OR PRYBARS TO LIFT THE COVER AWAY FROM THE TRANSFER CASE HOUSING THIS COULD SERIOUSLY DAMAGE THE MACHINED SEALING SURFACES AND RESULT IN THE TRANSFER CASE REASSEMBLED LEAKING WHEN Fig 24 24 Remove upper input shaft assembly from the transfer case housing To prevent damage store the upper input shaft in a secure area See Fig 24 NOTE 15 NECESSARY DISASSEMBLE FURTHER THE SHAFT ASSEMBLY UNLESS COMPONENTS ARE REPLACED SEE SECTION 5 3 FOR UPPER INPUT SHAFT DISASSEMBLY Fig 25 25 Remove the fifteen 15 bolts holding the rear carrier to the transfer case housing See Fig 25 Fig 26 26 Install four 4 7 16 14 NC bolts into the rear carrier and tighten equally to force the carrier from the transfer case housing See Fig 26 ZN CAUTION DO NOT USE SCREWDRIVERS OR PRYBARS TO LIFT THE COVER AWAY FROM THE TRANSFER CASE HOUSING THIS COULD SERIOUSLY DAMAGE THE MACHINED SEALING SURFACES AND RESULT IN THE TRANSFE
15. OUTPUT Fig 35 Fig 36 1 aid in proper reassembly use special tool 2 To aid in proper reassembly use special tool 866 750 and note the end float of the underdrive 866 749 and note the end float of the direct drive gear assembly before disassembly See Fig 35 gear assembly before disassembly See Fig 36 PRESS Fig 37 3 Engage the clutch collar gear into the underdrive gear Place the shaft assembly in a press such that the face of the clutch collar gear is supported by the separator and the press arbor is against the smaller threaded end of the shaft See Fig 37 4 Press the shaft through the bearings spacers underdrive gear and clutch collar gear PRESS Fig 38 5 Reinstall and engage the clutch collar gear into the direct drive gear Place the shaft assembly in a press such that the face of the clutch collar gear is supported and the press arbor is against the larger threaded end of the shaft See Fig 38 6 Press the shaft through the bearings spacers direct drive gear and clutch collar gear THIS CONCLUDES THE DISASSEMBLY OF THE REAR OUTPUT SHAFT 5 6 DISASSEMBLY OF THE FRONT OUTPUT SHAFT AND CARRIER Fig 39 1 To aid in proper reassembly note the amount of end float of the front output shaft and carrier assembly before disassembly See Fig 39 2 Remove the oil seal
16. R CASE LEAKING WHEN REASSEMBLED Fig 27 27 Remove the rear carrier Remove the oil seal from the rear carrier and discard Remove the bearing cups from the carrier only if necessary See Fig 27 Fig 28 26 Remove the rear lower output shaft and shifter shaft assembly from the transfer case housing To prevent damage to the shaft assembly store the assembly in a secure area See Fig 28 NOTE IT 15 NECESSARY DISASSEMBLE FURTHER THE SHAFT ASSEMBLY UNLESS ONE MORE COMPONENTS ARE TO BE REPLACED SEE SECTION 5 5 FOR REAR LOWER OUTPUT SHAFT DISASSEMBLY Fig 29 27 Remove the intermediate shaft assembly from the transfer case housing To prevent damage to the shaft assembly store the assembly in a secure area See Fig 29 NOTE 15 NOT NECESSARY TO DISASSEMBLE FURTHER THE SHAFT ASSEMBLY UNLESS COMPONENTS REPLACED SEE SECTION 5 4 FOR INTERMEDIATE DISASSEMBLY Fig 30 27 Remove the front declutch housing and if required any other gaskets shims caps carriers or bearing cups See Fig 30 THIS CONCLUDES THE GENERAL DISASSEMBLY OF THE TRANSFER CASE 5 2 DISASSEMBLY OF SUBASSEMBLIES During a normal overhaul it is neither necessary nor desireable to completely disassemble the shaft assemblies The bearing cone assemblies and the drive train gears are installed with a press fit to the shaft and their unnecessary removal only
17. ansfer case Position a transmission jack of suitable capacity beneath the transfer case The transfer case must be seated on the jack in a safe and firm position Disconnect transfer case mountings at the rubber shock insulators Since mounting designs vary consult the vehicle service manual After making sure that all mountings and connections to the transfer case disconnected lower the transfer case gradually to the floor It is imperative that the transfer case is ALWAYS safely positioned on the transmission jack to safeguard the transfer case from falling off the jack Remove the transfer case from beneath the vehicle It be necessary to jack the truck up to allow room to remove transfer case 4 3 2 INSTALLATION INTO THE 1 2 VEHICLE Place the transfer case onto the transmission jack preferably lifting by means of the eye bolts Position the transmission jack underneath the vehicle Some vehicles may require that one side be jacked up in order to achieve sufficient clearance to place the transfer case between the frame rails Raise the transmission jack to properly locate the transfer case Connect transfer case mountings Since mounting designs vary consult vehicle service manual Connect the drivelines Connect the speedometer cable Connect the shift cylinder air lines Connect the indicator light and temperature sensor wires Fill the housing with the appropriate lu
18. bricant to the correct level and install the level plug 10 Check the transfer case for leaks around the gaskets and seals NOTES ASBESTOS WARNING SUGGESTED PROCEDURES FOR WORKING WITH COMPONENTS SUSPECTED OF CONTAINING ASBESTOS Asbestos has been found to be a primary cause of various forms of respiratory disease and cancer of several vital body organs Primary ingestion is by breathing or swallowing dust containing fibers and can place smokers at a greater risk than those who do not smoke The onset of disease can be at an extended period of time several years after the exposure The Occupational and Safety Health Administration OSHA has established very stringent limitations for exposure to asbestos fibers by workers using the material and every precaution should be taken to minimize the risks involved The following are some suggested procedures to adopt when working with material that has or may be suspected of containing asbestos 1 Approved protective clothing gloves eye shield and aprons should be worn whenever working around the suspected material NIOSH 8 OSHA approved respirator masks suitable for asbestos dust should be worn at all times Disposable dust face masks not allowed by OSHA 2 Do not smoke while working on any asbestos related material or wearing protective apparel 3 not eat or drink food while wearing protective clothing Always wash before eating or drinking 4 Do not use
19. case lubricant should be changed on all new transfer cases after the first 3 000 to Above 10 F SAE 90 5 000 miles on highway or the first 40 hours off highway thereafter oil changes should be Below 10 F SAE 80 done at the following intervals Must be inhibited against corrosion oxidation and On Highway Service 10 000 15 000 Miles foan Off Highway Service Logging dirt moving 2 2 OFF HIGHWAY amp MINING mining and associated EQUIPMENT i ni 500 750 Hours 1 Heavy Duty Engine The recommended oil change and inspection periods are based on the average use and operating conditions that the unit may encounter It is suggested that the individual owner make a periodic lab analysis of the Above 10 SAE 50 lubricant to determine contamination based on the units specific operating conditions With this data the oil change and inspection periods can be better determined Temperature Grade Below 10 SAE 30 Be sure to specify heavy duty type meeting MIL L 2104B specifications 2 5 DRAINING THE OIL 2 Special Recommendation For extreme Draining is accomplished after the vehicle cold weather where temperature h d brief lowing the oil t istently below 0 F use SAE 20W heavy a DEEN operated Drey allowing ths 01 9 Ri il ti MIL L 2104B become warm and flow more freely Remove Z PAC AA WA 521 both drain and fill plugs Allow the housing to sp
20. cifications it will be necessary to disassemble the shaft and repeat steps 4 7 using a bearing spacer ring of a different thickness T lt Fig 48 9 After the gear float has been set correctly remove special tool 866 749 and install the rear output shaft spacer bearing 0006 special tool 866 751 and lock nut See Fig 48 10 Invert the rear output shaft assembly making sure that the clutch collar gear remains on the shaft 11 If removed during assembly press the bearing cups into the lower underdrive gear 12 Heat the bearing cones in an oven A CAUTION WHEN A PART IS ASSEMBLED WITH A PRESS FIT IT IS RECOMMENDED THAT THE PART BE PRIOR TO INSTALLATION IN A SUITABLE OVEN AT A TEMPERATURE NO GREATER THAN 300 HEATED COMPONENTS MUST BE ALLOWED TO COOL BEFORE END FLOAT MEASUREMENTS ARE MADE Fig 49 13 Install the inner bearing onto the end of the shaft followed by the bearing spacer ring See Fig 49 14 Install the lower under drive gear with bearing cups followed by an outer bearing cone 15 To set the lower underdrive gear end float use special tool 866 750 placed over the shaft Tighten the lock nut down Fig 50 16 Attach a dial indicator as shown and record the gear float by lifting up on the lower under drive gear The gear float should be 0 0005 0020 loose See Fig 50 17 the gear end float is not with
21. ecifications empty completely Before the unit is refilled it should be thoroughly flushed with clean flushing oil or kerosene NOTE EXTREME PRESSURE EP OILS ARE NO LONGER RECOMMENDED FOR USE IN FABCO TRANSFER CASES UNDER CERTAIN OPERATING CONDITIONS THESE OILS MIGHT FORM CARBON DEPOSITS ON GEARS SHAFTS If the unit is equipped with an oil pump the lube oil filter should be replaced whenever the oil is changed The element is of the spin on type A film of clean oil should be applied to the rubber gasket of the new element before installing Do not over tighten 2 6 2 7 REFILLING THE OIL If the transfer case has been removed from the vehicle for service it is best to refill the oil after the unit has been reinstalled into the vehicle Clean and replace the drain plug and fill the transfer case with the appropriate oil with the vehicle on level ground Fill the transfer case to the level of the fill plug The plug should be installed only after the oil level has stabilized For each transfer case the oil capacity will vary somewhat depending on the model and the inclination of the unit therefore always fill to the level of the fill plug Do not overfill Inspect for leaks OPERATING TEMPERATURE The operating temperature of the transfer case should not exceed 250 F 120 C Extensive operation at temperature exceeding 250 F will result in rapid breakdown of the oil and may shorten the transfer case li
22. ervicing and maintenance of components from any automotive vehicle present possible hazards every endeavor should be made to minimize the risks taken to successfully complete the task For your protection we offer these warnings and suggestions 1 When working on around or under the vehicle the parking brake should be securely applied and all wheels should be blocked to prevent wheel movement Do not rely on the vehicle being in gear with a dead engine to prevent movement All work should be performed on a flat level surface free of loose material 2 When working under a vehicle it should be raised and supported with the appropriate frame stands or very secure blocking WARNING NEVER WORK UNDER VEHICLE WHILE SUPPORTED ONLY ON A FLOOR JACK OR HOIST 3 Be sure any lifting equipment has adequate capacity to raise the vehicle or component being lifted This includes hydraulic floor jacks crane type hoists transmission jacks and axle support dollies etc The weight of Fabco components is given in the front of the applicable service manual 4 Caution must be exercised when cleaning the component or underside of the vehicle Compressed air should not be used to blow dirt away as any harmful contaminant material on the bottom of the vehicle will be spread around the work area Appropriate solvents and cleaning solutions can be used in accordance with their labeling instructions or by referring to the Material Safet
23. fe If reduction of operating speed is not acceptable then the case may have to be equipped with an external oil cooler to maintain the operating temperature below 250 F The following conditions may contribute to excessive oil temperature 1 Avehicle remaining stationary for extended periods while operating the power take off 2 vehicle which is used in tropical or desert conditions 3 vehicle where extended body work accumulation of dirt and plant material may shield the case from air ventilation and circulation 4 A vehicle that is operated for extended distances at high speed with the main transmission in overdrive 3 0 CLEANING INSPECTION 3 1 3 2 3 3 CLEANING Steam may be used for external cleaning of completely assembled units Care must be taken to ensure that water is kept out of the assembly by sealing breather caps and other openings The transfer case housing which is too large to conveniently clean with solvents may be immersed in a hot solution tank containing a mild alkaline solution Aluminum parts such as the carriers caps declutch housings and air shift cylinder components must never be cleaned in any type of alkaline solution Parts cleaned in a hot solution tank must be rinsed thoroughly to prevent damage by traces of alkaline material Parts with ground or polished surfaces such as bearings gears shafts and oil pump components should be cleaned with em
24. hift shaft access cover plate and shift cylinder bore cap with 1 4 20 bolts Torque to specification See Fig 104 Fig 105 42 If so equipped and removed during disassembly attach the oil filter mounting base Note the inlet and outlet positions as marked See Fig 105 Fig 106 43 If so equipped properly route and connect all lubrication lines Install the oil strainer See Fig 106 Fig 108 44 Attach the remaining shaft yokes The completed transfer case with pressure lubrication should appear as above See Figs 107 108 THIS CONCLUDES THE GENERAL ASSEMBLY OF THE TRANSFER CASE 6 7 ASSEMBLY OF THE OIL PUMP Fig 109 T Without the pressure relief spring installed position the pump cartridge assembly onto the end of the intermediate shaft See Fig 109 CAUTION THE CARTRIDGE PIN MUST MATE WITH THE SLOT ON THE INTERMEDIATE SHAFT Fig 111 3 Using a depth micrometer measure the distance between the outer face of the spacer ring and the pump cartridge assembly Record this measurement See Fig 111 4 Consult the following chart to determine the proper number of shims to use MEASUREMENT NO GAP MEASUREMENT SHIM QUANTITY 00 3 Shims Shims POSITIVE GAP SHIM QUANTITY Fig 110 MEASUREMENT 001 to 016 3 Shims 2 Place the spacer ring assembly with bushing 017 to 047 4 Shims s 048 078 5 Shims and gasket around the pump cartridge and against 07910 109 6 Shims the
25. in specifications it will be necessary to disassemble the shaft and repeat steps 14 16 using a bearing spacer ring of a different thickness Fig 51 18 After the gear float has been correctly remove special tool 866 750 and install the rear output shaft spacer bearing cone electronic speedometer drive gear See Fig 51 19 Set aside the rear output shaft assembly in an area where it will not be damaged 41111 the transfer case is ready to be assembled THIS CONCLUDES THE ASSEMBLY OF THE REAR OUTPUT SHAFT 6 5 ASSEMBLY OF THE FRONT OUTPUT AND CARRIER 1 Heat and install the inner bearing cone 5 Heat and install the outer bearing cone A CAUTION WHEN A PART IS ASSEMBLED WITH A PRESS FIT IT IS RECOMMENDED THAT THE PART HEATED PRIOR TO INSTALLATION IN A SUITABLE OVEN AT A TEMPERATURE NO GREATER THAN 300 F HEATED COMPONENTS MUST BE ALLOWED TO COOL BEFORE END FLOAT MEASUREMENTS ARE MADE Fig 53 6 To check shaft end float install special tool 866 751 Tighten the lock nut down See Fig 53 Fig 52 2 Install the bearing spacer ring against the bearing See Fig 52 NOTE IF THE END FLOAT CHECKED PRIOR TO DISASSEMBLY WAS WITHIN THE SPECIFIED LIMITS AND NO PARTS WERE REPLACED THE ORIGINAL BEARING SPACER RING MAY BE REUSED Fig 54 3 Press the bearing cups into the carrier 7 Attach a dial indicator as shown and record the shaft end float b
26. increases the likelihood of damage This caution also applies to the bearing cups installed in the carriers 5 3 DISASSEMBLY OF THE UPPER INPUT SHAFT 1 Remove the oil seal from the carrier and discard PRESS Remove the bearing cup from the carrier only if it is to be replaced PRESS m Fig 32 Fig 31 9 3 remove the rear bearing cone support the 2 Place the shaft assembly in a press such that the bearing cone with a separator and press the shaft rear of the gear is supported and the press arbor through the cone See Fig 32 bears against the threaded end of the shaft Remove the front bearing cone spacer and gear Remove the shaft key only if necessary See Fig 97 THIS CONCLUDES THE DISASSEMBLY OF THE UPPER INPUT SHAFT 5 4 DISASSEMBLY OF THE INTERMEDIATE SHAFT Fig 33 1 To remove the rear bearing cone spacer and the intermediate direct drive gear support the direct drive gear Press the shaft through the bearing spacer and gear Remove the shaft key only if necessary See Fig 33 PRESS Fig 34 2 Place the intermediate shaft assembly in a press such that the underdrive gear is supported and the press arbor bears against the end of the shaft Remove the front bearing cone and the underdrive gear Remove the shaft key only if necessary See Fig 34 THIS CONCLUDES THE DISASSEMBLY OF THE INTERMEDIATE SHAFT ASSEMBLY 5 5 DISASSEMBLY OF THE REAR
27. install the bearing cone assembly against the shoulder on the non threaded end of the upper input shaft See Fig 47 CAUTION WHEN A PART IS ASSEMBLED WITH A PRESS FIT IT IS RECOMMENDED THAT THE PART BE HEATED PRIOR TO INSTALLATION IN A SUITABLE OVEN AT A TEMPERATURE NO GREATER THAN 300 F U m 2 UB p R NB SQ SSS Fig 42 3 Invert the input shaft and install the heated gear spacer and the heated bearing cone See Fig 42 4 Set aside the upper input shaft assembly in an area where it will not be damaged until the transfer case is assembled THIS CONCLUDES THE ASSEMBLY OF THE UPPER INPUT SHAFT 6 3 ASSEMBLY OF THE INTERMEDIATE 1 removed reinstall the keys into the keyways of the intermediate shaft s 4 N 2 Heat the bearing cones intermediate direct TW drive gear and intermediate underdrive gear 22 UMA 5 BA CAUTION WHEN PART IS ASSEMBLED WITH A PRESS FIT IT IS RECOMMENDED THAT THE PART BE HEATED PRIOR TO INSTALLATION IN A SUITABLE OVEN AT A TEMPERATURE NO GREATER THAN 300 F 2 2 y gt p Fig 44 4 Invert the shaft and install the intermediate direct drive gear spacer and bearing cone See Fig 44 5 Set aside the intermediate shaft assembly in an area where it will not be damaged until the transfer case is ready to be assembled Fig 4
28. nd front declutch sliding gear into the declutch housing See Fig 77 Fig 78 19 Install the front drive shifter shaft into the declutch housing attaching it to the front declutch shift fork with two 2 special 7 16 20 bolts See Fig 78 22 Install the front drive shift spring plastic adjusting washer s and piston using a new o ring See Fig 82 Fig 80 20 Torque the shift shaft bolts to specification and lockwire See Figs 79 80 Fig 81 Fig 83 21 Install the front declutch shift cylinder adapter 23 Compress the shift spring by pushing down on into the declutch housing using new o rings the piston and install a 3 8 24 lock nut onto the end See Fig 81 of the shift shaft Torque the lock nut to specification See Fig 83 Fig 85 24 Install a new oil soaked felt wiper onto the piston Install the cylinder and cap over the piston Secure the assembly with four 4 1 4 20 bolts torquing to specification See Figs 84 85 WARNING WHEN INSTALLING THE CYLINDER OVER THE PISTON ASSEMBLY EXCERCISE CAUTION NOT TO NICK THE O RINGS OR DISTORT THE FELT WIPER FAILURE TO DO SO COULD RESULT IN A LEAKING FRONT DECLUTCH SHIFT CYLINDER Fig 86 25 Manually align the fixed and sliding clutch gears Apply air pressure 100 psi to the front drive declutch shift cylinder Check with feeler gages that there is a minimum of 0 005 clearance between both sides of the shift fork and the
29. onto a flat area of the rear carrier and check the shafts end float by carefully prying up on the intermediate shaft from underneath the transfer case The end float should read 0 003 0 008 loose See Figs 69 70 NOTE IF THE END FLOAT IS NOT WITHIN SPECIFICATION 0 003 0 008 loose THE SHIM PACK SHOULD BE REMOVED AND REPLACED WITH A SHIM COMBINATION WHICH WILL PROVIDE THE PROPER END FLOAT Fig 73 15 Turn the transfer case over Attach a dial indicator onto a flat area of the rear carrier adjacent to the rear output shaft yoke Check the end float on the rear output shaft The end float should read 0 003 0 008 loose See Fig 73 Fig 71 NOTE IF THE END FLOAT IS NOT WITHIN SPECIFICATION 0 003 0 008 LOOSE THE SHIM PACK SHOULD BE REMOVED AND REPLACED WITH A SHIM COMBINATION WHICH WILL PROVIDE THE PROPER END FLOAT Fig 72 14 Turn over the transfer case Install special tool 866 751 onto the end of the rear output shaft Install the bearing lock nut using special tool 4 866 687 006 See Figs 71 72 Fig 74 16 Torque the declutch housing attachment bolts to specifications See Fig 74 Fig 76 17 Using special tool 866 687 006 remove the bearing locknut on the rear output shaft Remove special tool 866 751 Install the front declutch fixed gear and the bearing lock nut Torque to specification See Figs 75 76 Fig 77 18 Install the front declutch shift fork a
30. shafts See Fig 57 58 Fig 62 5 Turn the transfer case over Install the Fig 59 Intermediate shaft assembly direct drive gear down into the transfer case See Fig 62 2 Place the stack of shims removed during disassembly on the intermediate and rear output shaft bores of the transfer case housing See Fig 59 6 Install a new locking plate between the fork and jam nut of the shifter fork assembly Fig 63 7 install the shifter shift fork assembly onto the rear output shaft assembly Make sure that the flat side of the shift fork faces the underdrive gear See Fig 63 Fig 64 8 Install the rear output shaft and shifter shaft fork assembly into the transfer case housing See Fig 64 9 If removed during disassembly install two 2 new short dowl pins into the transfer case housing Place a new rear carrier gasket onto the machine surfaces of the transfer case housing Install the rear carrier with bearing cups onto the transfer case Make sure the shifter shaft fork assembly is properly aligned See Fig 65 Fig 66 10 Install the carrier attaching hardware and torque to specifications See Fig 66 Fig 67 11 Install a rear output seal and the drive yoke Tighten the locknut to the specified torque See Fig 67 12 Gently tap the end of the intermediate shaft to properly seat it in the housing See Fig 68 Fig 70 13 Attach a dial indicator
31. tch sender unit and copper washer Using a pencil magnet remove sensor pin from the indicator switch sender hole See Fig 10 Fig 11 13 Remove access plate to the front declutch housing shift fork assembly See Fig 11 Fig 13 14 Remove the front declutch air cylinder disassembling piston spring and stops See Figs 12 amp 13 ZA CAUTION SPRING ASSEMBLY IS PRELOADED OBSERVE SAFETY PRECAUTIONS WHEN DISASSEMBLING Fig 14 15 Remove and discard the lock wire on the shift fork assembly Loosen but do not remove the two 2 bolts See Fig 14 Fig 17 18 Remove the fork and gear assembly from the front declutch housing See Fig 17 Fig 15 16 Remove the eight 8 bolts attaching the front output shaft carrier to the front declutch housing remove the front output shaft assembly and gasket from the transfer case See Fig 15 NOTE IT IS NOT NECESSARY TO DISASSEMBLE FURTHER THE SHAFT ASSEMBLY UNLESS ONE OR MORE COMPONENTS ARE TO BE REPLACED SEE SECTION 5 6 FOR FRONT OUTPUT SHAFT DISASSEMBLY Fig 16 Fig 19 17 Remove the two 2 bolts from the shift fork 19 Using special tool 866 687 006 remove the assembly Remove the shifter shaft from the front bearing lock nut from the front of the lower shaft declutch housing See Fig 16 See Figs 18 amp 19 Fig 20 20 Remove declutch gear from the front declutch housing See Fig 20 NOTE LEAVE THE FRONT DE
32. the front axle s and can be used in any configuration of rear driven axles The front drive axle can be engaged at any vehicle speed provided the rear wheels are not spinning however the vehicle must be stationary before the shift can be made between high and low ranges otherwise serious damage may occur The shifting between ranges and the engagement of front drive and power take off clutches is accomplished by air operated cylinders A Lubrication pump is optional on all models and may be used for oil circulation should an oil cooler installation be deemed necessary 1 2 SPECIFICATIONS The TC 270 transfer case is a two speed three shaft constant mesh design featuring a declutch for the front axle and underdrive engagement NOMINAL RATING Input Torque Input Horsepower Input Speed RATIOS Direct Underdrive GEAR TYPE SHAFT SIZES Input Front amp Rear Output SHAFT SPACING Drop SHIFT MECHANISM BEARINGS LUBRICATION LUBRICANT OIL CAPACITY DRY WEIGHT HOUSING OPTIONS 10 000 Lb Ft 350 HP 2 600 RPM 1 1 2 23 1 Helical Case 2 50 Inches 10 Parallel Spline 2 75 Inches 10 Parallel Spline 16 25 Inches Integral Air Cylinders Tapered Roller Splash See Section 2 0 11 Quarts U S 700 Lbs Cast Iron Full Power PTO Air Shifted Direct Mount SAE 4 Hydraulic Pump Drive Lubrication Pump amp Spin on Filter Standard with PTO
33. ulsion cleaners or petroleum solvents An alkaline solution may damage the machined surfaces and such cleaning methods should be avoided DRYING AND CORROSION INHIBITION Dry compressed air or clean soft shop towels should be used to dry parts after cleaning Bearings should never be spun dry with compressed air Dried parts should be immediately coated with a light oil or corrosion inhibitor to prevent corrosion damage Parts which are to be stored should also be wrapped in heavy waxed paper or plastic bags and kept dust free INSPECTION Prior to reassembly parts which are to be reused must be carefully inspected for signs of wear or damage Replacement of such parts can prevent costly downtime at a future date All bearing surfaces including roller bearing cups and cones should be examined for pitting wear or overheating Gears may also show pits as well as scoring and broken teeth Shafts may be nicked or marred or have damaged threads Parts which show any sign of damage should be repaired or replaced Inspect the rotor housing and idler of the oil pump if equipped for scoring Inspect the drive tab of the rotor assembly If any damage is noted the pump cartridge assembly should be replaced as a unit Check all shift forks and slots sliding clutches for wear or discoloration due to heat Check the engaging teeth for a partial engagement wear pattern 4 0 GENERAL INSTRUCTIONS 4 1 SAFETY The s
34. welders following typical and good workmanship procedures and safe practices 6235 75 SQ BROACH THRU SBE USE 13 16 DRILL LEO DETAL 0 25 03 X 45 5 75 _ VLA al A ID 535 48 4 PLCS x 90 240 Spa s ogge 0967 05 SEE DETAIL 1 MATERIAL 4140 HEAT TREAT Re 40 45 866 0687 006 BEARING LOCKNUT WRENCH REAR OUTPUT SHAFT 6238 06 X 45 4 PLACES MATERIAL MILD STEEL 866 0749 SETUP SLEEVE REAR OUTPUT SHAFT DIRECT DRIVE Pd 67236 866 0750 WELD MATERIAL MILD STEEL SETUP SLEEVE REAR OUTPUT SHAFT UNDERDRIVE 6 035 MATERIAL MILD STEEL 866 0751 SETUP SLEEVE REAR OUTPUT SHAFT 50 gt 05 x 45 CHAMFER 3 PLCS OUTSIDE 2 PLCS INSIDE 6 OAS go 3 96 g 2 79 4 MATERIA STEEL 06522 03 x 45 3 PLCS OUTSIDE 2 PLCS INSIDE 866 0752 SETUP SLEEVE FRONT OUTPUT SHAFT
35. y Data sheet MSDS that is available for each cleaner Approved protective eyewear gloves masks and clothing should always be wom 5 Fabco has not used Asbestos in any of its products manufactured since May of 1989 and was used only in axle brake linings prior to that time See the separate Asbestos Warning if you suspect asbestos may be present on the vehicle or component in the area to be serviced 4 2 ASSEMBLY PRECAUTIONS 1 Read the instructions completely before starting reassemble Refer to the appropriate exploded view in the parts manual 2 All parts must be clean The gasket surfaces must be free of old gasket material Do not reuse old gaskets 3 Bearing cup bores shaft splines and bearing mounting surfaces should be coated with Lubriplate or equivalent This is necessary to reduce the possibility of galling 4 used oil seals must be replaced the new oil seals should be coated with Loctite 601 or equivalent on their outer diameter prior to being installed in their bores The sealing lips should be coated with Lubriplate or the equivalent to provide initial lubrication 5 Any external cap screw not installed in a blind hole should have its threads coated with Permatex Form A Gasket 2 or an equivalent non hardening sealer to prevent an oil leak 6 threaded fasteners should be tightened to the torque specified in the torque chart 7 Any sharp edges the seal diameter of the universal
36. y lifting up on the carrier The shaft 4 Install the front output shaft into the carrier end float should be 0 003 0 008 loose See Fig 54 9 After the specified shaft end float is obtained remove the locknut and special tool 866 751 Install a new oil seal in the front output carrier Fig 55 Fig 56 NOTE IF SPECIAL TOOL 866 751 IS NOT 10 Reinstall 116 yoke and locknut torquing the AVAILABLE IT IS PERMISSIBLE TO USE THE locknut to the specified limit See Fig 56 FRONT OUTPUT SHAFT YOKE TO ACCOMPLISH THE SAME TASK See Fig 55 11 Set aside the front output shaft and carrier assembly in an area where it will not be damaged 8 If the shaft end float is not within specifications until the transfer case is ready to be assembled the carrier assembly will have to be disassembled and steps 2 7 repeated using a bearing spacer ring of a different thickness THIS CONCLUDES THE ASSEMBLY OF THE FRONT OUTPUT SHAFT AND CARRIER 6 6 GENERAL ASSEMBLY 2 4 A 3 Install the intermediate front cap to the transfer case Tighten but do not torque the bolts at this time See Fig 60 Fig 60 Fig 61 4 Install the front drive declutch housing noting its proper orientation refer to Fig 107 Tighten but do not torque the bolts at this time See Fig 61 Fig 58 1 If removed install bearing cups into the transfer case housing front bores for the intermediate and rear output
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