6-Speed Synchromesh Transmission Service Manual (FS-6406 Series) Issue 01/2003
Eaton 6-Speed Synchromesh Transmission Truck Components Operations Europe PO Box 11 Worsley Manchester M28 5GJ England Service Manual (FS-6406 Series)
Service Manual... 1 WARNING... 5 General View 6 Power Flow... 7 Introduction... 8 Purpose and Scope of Manual...8 How to Use This Manual...8 Warnings and Precautions...8 Disassemble Precautions... 8 Assemblies... 8 Bearings... 8 Cleanliness... 8 Input Shaft... 9 Snap Rings... 9 When Using Tools to Move Parts... 9 Inspection Precautions... 9 Recommended inspection procedures are provided in the following checklist...9 Bearings... 9 Bearing Covers... 9 Clutch Release Parts... 9 Gears... 9 Gear Shift Lever Housing Assembly... 10 Gray Iron Parts... 10 Oil Seals... 10 O-Rings... 10 Reverse Idler Gear Assemblies... 10 Shift Bar Housing Assembly... 10 Splines... 10 Synchroniser Assembly... 10 Washers... 10 Assemble Precautions... 10 Axial Clearances... 10 Bearings... 11 Capscrews... 11 Gaskets... 11 Initial Lubrication... 11 O-Rings... 11 Shims... 11 Universal Joint Companion Flange... 11 Model Designations... 12 Lubrication Information... 13 Torque Ratings... 13 Table 1 Torque Chart... 13 Maintain Proper Oil Level... 14 Maintenance Interval Chart... 14 Table 2 Maintenance Interval Chart... 14 Recommended Tools... 15 Preventive Maintenance... 16 Checks Before Transmission Removal... 16 Clutch Housing Mounting (1)... 16 Clutch Release Bearing (Not Shown)... 16 Clutch Pedal Shaft and Bores (3)... 16 Lubricant (4)... 17 Filler and Drain Plugs (5)... 17
Capscrews and Gaskets (6)... 17 Gear Remote Control (7)... 17 Checks With Drive Line Dropped...17 Universal Joint Companion Flange (9)... 17 Output Shaft... 17 Checks With Universal Joint Companion Flange Removed...17 Splines on Output Shaft (11)... 17 Mainshaft Rear Bearing Cover (12)... 17 Inspection...18 Table 5 Inspection Chart... 18 Rear Seal Maintenance... 19 Stand to hold gear box...20 In-Vehicle Service Procedures... 21 Shift Bar Housing...21 How to Remove the Remote Control Housing... 21 How to Install the Remote Control Housing... 21 How to Disassemble the Shift Bar Housing... 21 How to Assemble the Shift Bar Housing... 22 Output Yoke...22 How to Remove the Output Flange... 22 How to Remove the Output Flange (Continued)... 23 How to Install the Output Flange... 23 Clutch Housing...24 How to Remove the Clutch Housing... 24 How to Install the Clutch Housing... 24 Transmission Overhaul Procedures Bench Service... 25 Shift Bar Housing...25 Functions of a Shift Bar Housing... 25 How to Disassemble the Gear Remote Control... 25 How to Assemble the Gear Remote Control... 25 How to Disassemble the FS-6406 Shift Bar Housing... 26 How to Assemble the FS-6406 Shift Bar Housing... 27 How to Disassemble the Reverse Plunger... 29 How to Assemble the Reverse Plunger... 30 Disassemble Main Section... 31 How to Remove the Input Shaft Assembly... 31 How to Remove the Mainshaft Assembly... 31 How to Remove the Countershaft Assembly... 32 How to Remove the Reverse Idler Gear Assembly.... 33 Mainshaft Assembly special tools... 34 How to Disassemble the FS-6406 Mainshaft Assembly... 34 How to Disassemble the FS-6406 Mainshaft Assembly..36 How to Assemble the FS-6406 Mainshaft Assembly special tools 37 How to Assemble the FS-6406 Mainshaft Assembly...38 How to Assemble the FS-6406 Mainshaft Assembly...39 Countershaft Assembly... 40 How to Disassemble the FS-6406 Countershaft Assembly... 40 How to Disassemble the FS-6406 Countershaft Assembly.....41 How to Assemble the FS-6406 Countershaft Assembly... 42 How to Assemble the FS-6406 Countershaft Assembly... 43 Assemble Main Section... 43 How to Install the Reverse Idler Gear Assembly... 43 How to Install the Countershaft Assembly... 44 Countersahft assembly end play by Model... 45 3
How to Install the Mainshaft Assembly... 45 How to Install the Mainshaft Assemble... 46 How to Install the Input Shaft Assembly... 47 Setting End Play Procedure... 48 Mainshaft end play... 48 4
WARNING 5
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Power Flow The transmission must efficiently transfer the engine s power, in terms of torque, to the vehicle s wheels. Knowledge of what takes place in the transmission during torque transfer is essential when trouble-shooting and when making repairs become necessary. Power flow on 5 speed transmissions 1. Power (torque ) from the engine is transferred to the transmission input shaft. 2. Torque is transferred to countershaft drive gear. 3. Torque is delivered along countershaft to all countershaft gears. 4. Torque is transferred to engaged mainshaft gear. The cross section view illustrates 1 st speed gear position. 5. The engaged mainshaft gear external clutching teeth transfer torque to the mainshaft through the synchroniser assembly or sliding clutch. 6. The mainshaft transfer torque directly to driveshaft through the output yoke. 7
Purpose and Scope of Manual This manual is designed to provide detailed information necessary to service and repair the Eaton Fuller transmission listed on the front. How to Use This Manual The service procedures have been divided into two sections: In-Vehicle Service Procedures and Transmission Overhaul Procedures Bench Service. In-Vehicle Service Procedures contain procedures that can be performed while the transmission is still installed in the vehicle. Transmission Overhaul Procedures contain procedures that are performed after the transmission has been removed from the vehicle. The procedure sections are laid out with a general heading at the top outside edge of each page followed by more specific headings and the procedures. To find the information you need in these sections, first go to the section that contains the procedure you need. Then look at the heading at the top and outside edge of each page until you find the one that contains the procedure you need. Transmission Overhaul Procedures follow the general steps for complete disassembly and then assembly of the transmission. NOTE: In some instances the transmission appearance may differ from the illustrations. The procedure is the same. Warnings and Precautions Disassemble Precautions It is assumed in the detailed assembly instructions that the lubricant has been drained from the transmission, the necessary linkage disconnected and the transmission has been removed from vehicle chassis. Removal of the gear shift lever housing assembly (or remote control assembly) is included in the detailed instructions (How to Remove the Gear Shift Lever). This assembly MUST be detached from the shift bar housing before transmission can be removed. Follow closely each procedure in the detailed instructions, make use of the text, illustrations, and photographs provided. Assemblies When disassembling the various assemblies, such as the mainshaft, countershafts, and shift bar housing, lay all parts on a clean bench in the same sequence as removed. This procedure will simplify assembly and reduce the possibility of losing parts. Bearings Carefully wash and lubricate all usable bearings as removed and protectively wrap until ready for use. Remove bearings planned to be reused with pullers designed for this purpose. Cleanliness Provide a clean place to work. It is important that no dirt or foreign material enters the unit during repairs. Dirt is an abrasive and can damage bearings. It is always good practice to clean the outside of the unit before starting the planned disassembly. 8
Input Shaft The input shaft can be removed from the transmission without removing the countershaft or mainshaft. Snap Rings Remove snap rings with pliers designed for this purpose. Snap rings removed in this manner can be reused, if they are not sprung or loose. When Using Tools to Move Parts Always apply force to shafts, housings, etc., with restraint. Movement of some parts is restricted. Never apply force to driven parts after they stop solidly. The use of soft hammers, soft bars, and mauls for all disassembly work is recommended. Inspection Precautions Before assembling the transmission, check each part carefully for abnormal or excessive wear and damage to determine reuse or replacement. When replacement is necessary, use only genuine Eaton Fuller Transmission parts to assure continued performance and extended life from your unit. Since the cost of a new part is generally a small fraction of the total cost of downtime and labour, avoid reusing a questionable part which could lead to additional repairs and expense soon after assembly. To aid in determining the reuse or replacement of any transmission part, consideration should also be given to the unit s history, mileage, application, etc. Recommended inspection procedures are provided in the following checklist. Bearings A. Wash all bearings in clean solvent. Check balls, rollers, and raceways for pitting, discoloration, and spalled areas. Replace bearings that are pitted, discoloured, spalled, or damaged during disassembly. B. Lubricate bearings that are not pitted, discoloured, or spalled and check for axial and radial clearances (per manufacturers specifications. C. Replace bearings with excessive clearances. D. Check bearing fit. Bearing inner races should be tight to shaft; outer races slightly tight to slightly loose in case bore. If bearing spins freely in bore, case should be replaced. Bearing Covers A. Check covers for wear from thrust of adjacent bearing. Replace covers damaged from thrust of bearing outer race. B. Check cover bores for wear. Replace those worn or oversized. Clutch Release Parts A. Check clutch release parts. Replace yokes worn at cam surfaces and bearing carrier worn at contact pads. B. Check pedal shafts. Replace those worn at bushing surfaces. Gears A. Check gear teeth for frosting and pitting. Frosting of gear teeth faces presents no threat of transmission failure. Often in continued operation of the unit, frosted gears heal and do not progress to the pitting stage. In most cases, gears with light to moderate pitted teeth have considerable gear life remaining and can be reused, but gears in the advanced stage of pitting should be replaced. 9
B. Check for gears with clutching teeth abnormally worn, tapered, or reduced in length from clashing during shifting. Replace gears found in any of these conditions. C. Check axial clearance of gears. Where excessive clearance is found, check gear snap ring, split washer, clutch hub, and gear hub for excessive wear. Gear Shift Lever Housing Assembly A. Check spring tension on shift lever. Replace tension spring if lever moves too freely. B. If housing is disassembled, check gear shift lever bottom end, housing, and shift finger assembly for wear. Replace if excessively worn. Gray Iron Parts A. Check all grey iron parts (case, covers) for cracks and breaks. Replace parts found to be damaged. Oil Seals A. Check oil seal in input shaft and rear bearing cover. If sealing action of lip has been destroyed, replace oil seal. O-Rings A. Check all O-rings for cracks or distortion. Replace if worn. Reverse Idler Gear Assemblies A. Check for excessive wear from action of roller bearings. Shift Bar Housing Assembly A. Check for wear on shift yokes and finger assembly at pads and lever slot. Replace excessively worn parts. B. Check yokes for correct alignment. Replace sprung yokes. C. Check lockscrews in yoke assembly retainer plates. Tighten those found loose. Replace shift bar housing if lockscrew holes are damaged. D. Check detent ball hole for wear. Replace if bore is oblong. Splines A. Check splines on all shafts for abnormal wear. If sliding clutches, gears, clutch plates, companion flange, or clutch hub has worn marks in the spline sides, replace the specific shaft affected. Synchroniser Assembly A. Check synchroniser for burrs, uneven and excessive wear at contact surface, and metal particles. B. Check blocker pins and pre-energiser springs for excessive wear or looseness. C. Check synchroniser contact surfaces on the synchroniser cups for wear. Washers A. Check surfaces of all washers. Washers scored or reduced in thickness should be replaced. Assembly Precautions Make sure that case interiors and housings are clean. It is important that dirt and other foreign materials are kept out of the transmission during assembly. Dirt is an abrasive and can damage polished surfaces of bearings and washers. Use certain precautions, as listed below, during assembly. Axial Clearances Maintain original axial clearances for mainshaft gears. 10
Bearings Use a sleeve type bearing driver for bearing installation. These special drivers contact the inner bearing race, preventing damage to balls/rollers while maintaining correct bearing alignment with shaft. Capscrews To prevent oil leakage and loosening, use Eaton/Fuller sealant Loctite 262 on all capscrews, if not precoated. Gaskets Use new gaskets throughout the transmission as it is being rebuilt. Make sure all gaskets are installed. An omission of any gasket can result in oil leakage or misalignment of bearing covers. Initial Lubrication Coat all thrust washers, synchronisers, and bearings with transmission lubricant during assembly to prevent damage during initial start-up. O-Rings Lubricate all O-rings with silicon lubricant. Shims Apply a light coat of Eaton/Fuller sealant Loctite 518 or 515 to both sides of shims. Universal Joint Companion Flange Pull the companion flange or yoke tightly into place with the output shaft nut, using (645-711 Nm) of torque. Make sure the speedometer drive gear or a replacement spacer of the same width has been installed. Failure to properly torque the nut can result in damage to the mainshaft rear bearing. IMPORTANT: See the appropriate Illustrated Parts Lists (specified by model series) to ensure that proper parts are used during assembly of the transmission. 11
Serial Tag Information and Model Nomenclature Transmission model designation and other transmission identification information are stamped on the transmission tag. To identify the transmission model designation and serial number, locate the tag on the transmission and then locate the numbers as shown below When calling for service assistance or parts, have the model and serial numbers handy. Do not remove or destroy the transmission identification tag. Transmission Tag and Location Model Number The model number gives basic information about the transmission and is explained below. Use this number when calling for service assistance or replacement parts. Serial Number The serial number is the sequential identification number of the transmission. Before calling for service assistance, write the number down. It may be needed. FS-6406 F S O 6 4 0 6 A Bill of Material or Customer Number This number is also referred to as the TA# and is located below the model and serial numbers. It is a reference number used by Eaton and is helpful if calling for technical support. 12
Torque Ratings Correct torque application is extremely important to assure long transmission life and dependable performance. Over-tightening or under-tightening can result in a loose installation and, in many instances, eventually cause damage to transmission gears, shafts or bearings. Use of a thread sealer/locking compound is recommended for all capscrews. Do not torque capscrews dry. Torque Chart Description Torque Value Nm Thread Additional Comments Size 6 Front Bearing Cover 21-27.Nm 5/16-18 Apply Loctite 262 to threads Capscrews 4 Shift Lever Housing 28-33.Nm 3/8-16 Apply Loctite 262 to threads. Capscrews 9 Shift Rail Retainer 28-33.Nm 3/8-16 Apply Loctite 262 to threads. Capscrews 17 Shift Bar Housing 48-54.Nm 3/8-16. Apply Loctite 262 to threads Capscrews 1 Output Shaft Nut 645-711Nm 1 ¼--18 With nylon locking insert. Oiled at vehicle installation. 4 Clutch Housing Nuts 149-181Nm 5/8-16 Apply Loctite 262 to threads. 2 Hand Hole Cover 7-10Nm ¼-12 Apply Loctite 262 to threads. Capscrews 4 Mainshaft Rear Bearing 82-88Nm ½-32. Apply Loctite 262 to threads Cover Capscrews 1 Oil Fill Plug 34-47Nm ¾ Pipe 1 Oil Drain Plug 62-67Nm ¾ Pipe 4 Countershaft Rear Bearing Cover 48-54Nm 3/8-16 Use plain flat washers. Apply Loctite 262 to threads. Capscrews 12 PTO Cover Capscrews 14-27Nm 3/8-16 Apply Loctite 262 to threads. 13
Proper lubrication procedures are the key to a good all-around maintenance program. Eaton Fuller Transmissions are designed so that the internal parts operate in an oil circulating bath created by the motion of the gears and shafts. All parts will be properly lubricated if these procedures are closely followed: A. Maintain oil level. Inspect regularly. B. Follow maintenance interval chart. C. Use the correct grade and type of oil. D. Buy from a reputable dealer. Maintain Proper Oil Level Make sure oil is level with the filler opening. Being able to reach oil with your finger does not mean oil is at proper level. (25.4mm of oil level is about 3,8litres.) When adding oil, never mix engine oils and gear oils in the same transmission. 1. Incorrect 2. Correct Maintenance Interval Chart Transmission Oils See Service and Maintenance Manual If your vehicle has a transmission oil filter, you must change the filter when fluid or lubricant is changed. The use of lubricants not meeting these requirements will affect warranty coverage. 14
Some repair procedures pictured in this manual show the use of specialised tools. Their actual use is recommended as they make transmission repair easier, faster, and prevent costly damage to critical parts. But for the most part, ordinary mechanic s tools such as socket wrenches, screwdrivers, etc., and other standard shop items such as a press, mauls and soft bars are all that is needed to successfully disassemble and reassemble any Eaton Fuller Transmission. 15
Everyday there are countless vehicles operating over the highways with transmissions in such a neglected mechanical condition, they can be referred to as failures looking for a place to break down. They lack a proper and organised preventive maintenance program. Preventive maintenance is a general term which applies to all procedures necessary to have maximum life and satisfactory service at the lowest possible cost, short of removing and repairing the unit. A number of conditions contrary to good preventive maintenance can generally be pointed to when inspecting a failed transmission. Taking a few minutes every so many hours or miles to do a few simple checks could help avoid eventual breakdown or reduce the repair cost. If the transmission is not cared for, it will breakdown. Transmission appearance may differ, however the procedure is the same. Checks Before Transmission Removal NOTE: Transmission appearance may differ, the procedure is the same. 6 Clutch Housing Mounting (1) Check all cap screws of clutch housing flange for looseness. Clutch Release Bearing (Not Shown) Remove hand hole cover and check radial and axial clearance in release bearing. Check relative position of thrust surface of release bearing with thrust sleeve on push-type clutches. Clutch Pedal Shaft and Bores (3) Pry upward on shafts to check wear. If excessive movement is found, remove clutch release mechanism and check bushings on bores and wear on shafts. See Original Truck Builder literature. 16
Lubricant (4) Change at specified service intervals. Use only the types and grades as recommended. Filler and Drain Plugs (5) Remove filler plugs and check level of lubricant at specified intervals. Tighten fill and drain plugs securely. Capscrews and Gaskets (6) Check all capscrews, especially those on PTO covers and rear bearing covers for looseness which would cause oil leakage. Check PTO opening and rear bearing covers for oil leakage due to faulty gasket. Gear Remote Control (7) Check for looseness and free play in housing. If lever is loose in housing, check Gear remote control Housing Assembly. Checks With Drive Line Dropped (prop shaft removed) Universal Joint Companion Flange (9) Check for tightness. Tighten to recommended torque. Output Shaft (Yoke Nut Tightened) Pry upward against output shaft to check radial clearance in mainshaft rear bearing. Checks With Universal Joint Companion Flange Removed NOTE: If necessary, use solvent and shop rag to clean sealing surface of companion flange or yoke. Do not use crocus cloth, emery paper, or other abrasive materials that will mar surface finish. Splines on Output Shaft (11) Check for wear from movement and chucking action of the universal joint companion flange or yoke. Mainshaft Rear Bearing Cover (12) Check oil seal for wear. 17
Inspection Part to Inspect What to Check For Action to be Done Speedometer Connections Speedometer cables should not be loose Applied hydraulic thread sealant 71208 to threads. Torque speedometer sleeve to Should be an O-ring or gasket between the mating Speedometer sleeve and the rear bearing cover. 47-67 Nm Replace the O-ring/gasket if damaged or missing. Rear Bearing Cover Nuts Check retaining nuts for tightness. Apply Eaton Sealant Loctite 262 to the cap screw threads. Torque cap screws to 82 94 Nm Output Yoke Retaining Nut PTO Covers and Openings Front Bearing Cover Oil Drain Plug, Oil Fill Plug Check the output yoke retaining nut for tightness. Check the cap screws for tightness. Check front bearing cover, front case, shift bar housing, rear bearing cover, and clutch housing for cracks or breaks. Check the capscrews for tightness. Check the oil drain plug and the oil fill plug for leakage. Torque the output yoke retaining nut to 645-711 Nm. Do not over torque the output nut. Apply Eaton Sealant Loctite 262 to the cap screw threads, if not precoated. Tighten PTO capscrews to 14 27 Nm Replace parts found to be damaged. Tighten the cap screws to 21-33 Nm Torque the oil drain plug to 62 74 Nm Torque the oil fill plug to 34 47 Nm 18
Rear Seal Maintenance Leakage in transmission rear seals is perhaps the most common problem in truck transmissions. The problem is more than a nuisance because if not repaired, a leaking seal can lead to catastrophic transmission failure. There have been strides in reducing leakage through improved designs and the use of new seal materials. However, the most important way to reduce this problem continues to be through proper service and installation procedures. It can be very time consuming and expensive to replace a rear seal system, then find the oil seal system was not causing the oil leakage. Using the following checklist, inspect the transmission to insure proper identification of the leak path. Before disassembling the rear seal system, clean the rear bearing cover, the rear seal, and the output yoke. DO NOT USE A HIGH PRESSURE SPRAY WASHER TO CLEAN THE REAR SEAL SYSTEM. USE A CLEAN DRY CLOTH. Run the vehicle, then inspect these areas for oil leaks. 19
Place the Transmission on the stands, 1000 Use Tool 2237
Shift Bar Housing How to Remove the Remote Control Housing Special Instructions 1. From the remote control base, remove the four (4) retaining capscrews. 2. To break the gasket seal, lightly lever the gear shift lever housing. 3. Remove the gear shift lever housing. 4. Remove the gasket and clean all mounting surfaces of gasket material. How to Install the Remote Control Housing Special Instructions Make sure the shift block and yoke notches are aligned in the neutral position. 1. Position a new remote control gasket on the remote control mounting surface. 2. Fit the remote control finger into the shift block. 3. Apply Loctite 262 or equivalent to the retaining capscrews, if not precoated. 4. Install the retaining capscrews, tighten to 28 33 Nm of torque. Final Check Make sure the capscrews are properly torqued. Make sure you can shift the transmission. How to Disassemble the Shift Bar Housing Special Instructions There are two (2) lengths of capscrews. The 1 ½ capscrews are used with the lifting eyes. Note their location. Shift transmission into neutral position. 1. From the shift bar housing rim, remove the retaining capscrews. 2. To break the gasket seal, jar the shift bar housing. 3. Remove the shift bar housing. 4. Remove the gasket and clean all mounting surfaces of gasket material. 21
How to Assemble the Shift Bar Housing Special Instructions There are two (2) lengths of capscrews. The 1 ½ capscrews are used with the lifting eyes. Apply Loctite 518 or equivalent to shift bar housing gasket before assembly. 1. Place the shift bars in the neutral position. 2. Place the synchronisers in the neutral position (refer to picture). 3. Position a new shift bar housing gasket on the shift bar housing mounting surface. 4. As you install the shift bar housing, make sure the yokes fit onto the corresponding synchronisers. Final Check Make sure the capscrews are properly torqued. Output Yoke How to Remove the Output Flange Special Instructions You must remove the shift bar housing in order to lock the transmission. Special Tools A large breaker bar or air impact wrench 5. Apply Loctite 262 or equivalent to the capscrews, if not precoated. 6. Install the centre rear retaining capscrew first and the centre front retaining capscrew second, tighten to 48-54 Nm torque 7. Install the remaining capscrews, tighten to 48 54 Nm of torque. 22
How to Remove the Output Flange (Continued) 1. Engage two (2) mainshaft synchronisers into two (2) mainshaft gears to lock the transmission. 2. Use a breaker bar 9134 to hold the flange and remove the nut from the output shaft. 3. Pull the output yoke or flange straight to the rear and off the output shaft. How to Install the Output Flange Special Instructions You must remove the shift bar housing in order to lock the transmission. Special Tools Torque wrench with 680 Nm capacity Final Check Make sure the output shaft nut is properly torqued. Unlock the transmission. 1. Engage two (2) mainshaft synchronisers into two (2) mainshaft gears to lock the transmission. 2. Install the speedometer drive gear rotor or replacement spacer on the output shaft inside the rear bearing cover. 3. Slide the companion flange or yoke onto the output shaft. 4. Install the output shaft nut, tighten to 645-711 Nm 23
Clutch Housing How to Remove the Clutch Housing Special Instructions Removal of the clutch housing is done in the horizontal position. 1. Remove the four clutch housing retaining bolts from the case and clutch housing. 2. Jar clutch housing with a rubber mallet and pull the clutch housing from transmission case. How to Install the Clutch Housing 1. Position clutch housing on front of transmission. 2. Install four retaining bolts and torque to the recommended torque. 24
Shift Bar Housing Functions of a Shift Bar Housing Shift bar housings are a very important part of the transmission. No matter what kind of shift bar housing your transmission has, they all provide the same functions: Engage the transmission gearing, Prevents the driver from shifting into 2 gears at the same time, Prevents shifting into reverse without force, Actuates the back up lights, Actuates the neutral switches. How to Disassemble the Gear Remote Control 25
How to Disassemble the FS-6406 Shift Bar Housing Special Instructions The shift bar housing must be removed from the transmission. During disassembly, lay all parts on a clean bench in order of removal to facilitate assembly. Shift bars not being removed must be kept in the neutral position or the interlocking parts lock the bars. Start with reverse yoke assembly. When removing the interlock balls, detent balls, and springs, remove the interlock and detent balls before removing the springs. 1. With the housing rear to the right, lay the assembly on a flat surface. 2. In order to remove the front retaining capscrews, shift 5 th 6 th yoke assembly into 5 th gear position (rearward). 3. Remove capscrews and retainers. 4. Remove reverse yoke assembly. 5. Remove 1 st 2 nd yoke assembly and interlock pin. 6. Remove 3 rd 4 th yoke assembly and interlock pin. 7. Remove 5 th 6 th yoke assembly. 26
How to Disassemble the FS-6406 Shift Bar Housing (Continued) 8. Inspect the yoke pad bushings. If the pads are worn, remove worn pad from shift yoke, install new pad and bend tabs over yoke top and bottom. 9. Inspect the yokes. If the yokes are damaged, remove by driving the roll pin through the yoke and rail. 10. Remove the interlock balls, detent balls, and springs. How to Assemble the FS-6406 Shift Bar Housing Special Instructions Interlock balls, detent balls, and springs can be used interchangeably. Lubricate yoke pads and inserts with oil before assembly. Lubricate yoke bar grooves with grease before assembly. Keep yoke bars in neutral while assembling. The shift yoke retainer holes are not tapped on new shift bar housings. The capscrews that are used are thread forming and can be reused if the shift bar housing is replaced. It may be necessary to support the yoke bars in position while installing the retainers. 1. Install interlock balls, detent balls and springs in the following sequence; C Position (2) balls in adjacent cross bore. Install reverse detent spring and ball Position (3) balls in the reverse light switch bore. D. Repeat steps B and C for 1 st -2 nd position, 3 rd -4 th position, and 5 th -6 th position. NOTE: Balls and springs can be used interchangeably. 27
How to Assemble the FS-6406 Shift Bar Housing (Continued) 2. Position reverse yoke in housing assembly as shown. 3. Install the interlock pin in 1 st -2 nd yoke assembly. 4. Position 1 st -2 nd yoke in housing assembly. 5. Install the interlock pin in 3 rd -4 th yoke assembly. 6. Position 3 rd -4 th yoke in housing assembly. 7. Position 5 th -6 th shift block in housing assembly. 8. Position retainers, front retainer in rear set of holes. 9. Install the capscrews in the middle and rear retainers. Tighten all rail support capscrews to 27-34 Nm. NOTE: It may be necessary to support rails in proper position while installing rail supports. 10. Carefully shift the 5 th -6 th yoke into 5 th gear position (rearward). 11. Install the capscrews in front retainer. Tighten all rail support capscrews to 27-34 Nm. Final Check Make sure interlocking system is working cannot shift into 2 gears at the same time. 28
How to Disassemble the Reverse Plunger Special Instructions Snap ring and retainer are under spring pressure. 1. Depress reverse plunger springs and retainer. 2. Remove snap ring and spring retainer. 3. Remove the reverse plunger springs. 4. Remove washer and plunger. 5. Inspect reverse plunger parts. Replace worn or damaged parts. 29
How to Assemble the Reverse Plunger Special Instructions Place the reverse yoke bar in a vice. Special Tools Vice with brass jaws or wood blocks 1. Install plunger and washer. 2. Install reverse plunger springs. 3. Depress the reverse plunger retainer and springs. 4. Install the snap ring in the shift block groove. Final Check Make sure snap ring is securely in shift block groove. 30
Disassemble Main Section How to Remove the Input Shaft Assembly 1. Turn out six cap screws; jar front bearing cover with a rubber mallet and remove. If necessary remove oil seal from cover. 2. If necessary remove bearing race from front bearing cover Use Tool 2546. 3. Remove input shaft assembly from transmission. 4. Using a Tool 0827, remove bearing cage and rollers. Install bearing puller and remove bearing race from input shaft. 1. Turn out four retaining nuts and lockwashers. Using screwdrivers in notches, remove rear bearing cover. If necessary remove oil seal from cover. 2. Remove shims and speedometer drive gear or rotor. NOTE: Shims may come off with rear bearing cover. 3. Wrap a sling around the 3 rd -4 th synchroniser assembly. Use a hoist to remove the mainshaft assembly from the case. 31
How to Remove the Countershaft Assembly 1. Turn out capscrews, remove countershaft rear bearing cover and shims. 2. Remove the countershaft rear bearing cup. NOTE: Countershaft may slide to the rear and out of bearing bore. 3. Move countershaft assembly to the rear and lift it from the case. 4. If countershaft front bearing race is to be replaced, drive core plug through front of transmission use tool 3016 and 2363 and drive the race to the rear toward the inside of the case. 32
How to Remove the Reverse Idler Gear Assembly FS 6406 33
Mainshaft Assembly How to Disassemble the FS-6406 Mainshaft Assembly Special Instructions During disassembly, lay all parts on a clean bench in order of removal to facilitate reassemble. Special Tools Vice with brass jaws or wood blocks Snap ring pliers Bearing puller
How to Disassemble the FS-6406 Mainshaft Assembly (Continued) 1. With mainshaft front facing up, install the mainshaft assembly vertically in a vice. 2. Remove 5 th -6 th speed synchronizer and cups. 2. Using a puller mounted behind 5 th -6 th clutch hub, remove hub and bearing. 4. Remove 5 th gear and bearings. 5. Remove snap ring, thrust washer, and locating ball. 6. Remove 4 th gear and bearings. 7. Remove 3 rd -4 th speed synchronizer and cups. 8. Remove snap ring and 3 rd -4 th clutch hub. 9. Remove 3 rd gear and bearings. 10. Remove snap ring, thrust washer, and locating ball. 11. Remove 2 nd gear and bearings. 12. Remove lst-2 nd speed synchroniser. Use tool 0827 1. Front Bearing 9. 3 rd -4 th Speed Synchroniser and Cups 2. 5 th -6 th Speed Synchroniser and Cups 10. 3 rd -4 th Clutch Hub 3. 5 th -6 th Clutch Hub 11. 3 rd Gear 4. 5 th Gear 12. 2 nd Gear 5. Gear Bearing 13. 1 st 2 nd Speed Synchroniser 6. Snap Ring 14. Mainshaft 7. Thrust Washer and Locating Ball 8. 4 th Gear 35
How to Disassemble the FS-6406 Mainshaft Assembly (Continued) 13. With mainshaft rear facing up, install the mainshaft assembly vertically in a vice. 3 14. Using a puller, remove reverse gear, washer, and rear bearing. 15. Remove reverse gear bearing and sliding clutch. 16. Remove snap ring and clutch hub. 17. Remove 1 st gear and bearings. 8 Use Tools 0833, 2381. 1. Rear Bearing 6. Snap Ring 2. Washer 7. 1 st Gear Clutch Hub 3. Reverse Gear 8. 1 st Gear 4. Gear Bearing 9. Main shaft 5. Sliding Clutch 36
How to Assemble the FS-6406 Mainshaft Assembly Special Instructions Lubricate the gear bearing bores, gear hub faces, synchronizer friction surfaces, synchronizer cups and the mainshaft with transmission lube as the mainshaft is assembled. Do not heat reverse bearing race over 160 C. Special Tools Vice with brass jaws or wood blocks Sleeve type bearing driver (FL2513) Snap ring pliers 37
How to Assemble the FS-6406 Mainshaft Assembly (Continued) 1. With mainshaft rear facing up, install the mainshaft assembly vertically in a vice. 2. Install 1 st gear bearings. 3. With 1 st gear clutching teeth down, install 1 st gear. 4. With reverse gear clutch hub notched teeth facing down, install clutch hub. 5. Install snap ring. 6. With reverse gear sliding tapered clutching teeth facing up, install sliding clutch. 7. Install reverse gear bearing. 8. With reverse gear clutching teeth facing down, install reverse gear. 9. Install reverse gear washer. Washer can be installed either way. 10. Use a sleeve type driver or heat lamp and install the rear mainshaft bearing. 1. Rear Bearing 6. Snap Ring 2. Washer 7. 1 st Gear Clutch Hub 3. Reverse Gear 8. 1 st Gear 4. Gear Bearing 9. Mainshaft 5. Sliding Clutch Use Tool FL 2513 38
How to Assemble the FS-6406 Mainshaft Assembly (Continued) 11. With mainshaft front facing up, install the mainshaft assembly vertically in a vice. 12. Install the 1 st -2 nd synchroniser. A. Slide synchroniser part way on mainshaft to engage one sliding clutch spline teeth on the mainshaft spline teeth. B. Slide the synchroniser centre plate on the mainshaft aligning the three internal fingers with the three mainshaft grooves to get it started. C. Rotate the 2 nd sliding clutch using fingers so it engages the splines on the mainshaft and position centre plate axially to the mainshaft spline teeth centre. 13. Install 2 nd gear bearings. 14. With 2 nd gear clutching teeth down, install 2 nd gear. 15. Install locating ball and washer in mainshaft groove. Washer can be installed either way. 16. Install snap ring in mainshaft groove. 17. Install 3 rd gear bearings. 18. With 3 rd gear clutching teeth up, install 3 rd gear. 19. With 3 rd -4 th clutch hub stepped face up, install 3 rd - 4 th clutch hub. 20. Install snap ring in mainshaft groove. 21. Install 3 rd -4 th speed synchronizer and cups. 22. Install 4 th gear bearings. 23. With 4 th gear clutching teeth down, install 3 rd gear. 24. Install locating ball and washer. Washer can be installed either way. 1. Front Bearing 25. Install snap ring in mainshaft groove. 2. 5 th -6 th Speed Synchroniser and Cups 26. Install 5 th gear bearings. 3. 5 th -6 th Clutch Hub 27. With 5 th gear clutching teeth up, install 5 th gear. 4. 5 th Gear 28. With 5 th -6 th clutch hub flat surface facing up, 5. Gear Bearing 2 install 5 th -6 th clutch hub. 6. Snap Ring 29. Install 5 th -6 th speed synchroniser and cups. 7. Thrust Washer and Locating Ball 30. Use a sleeve type driver and install the front 8. 4 th Gear mainshaft bearing. 9. 3 rd -4 th Speed Synchroniser and Cups 10. 3 rd -4 th Clutch Hub 11.3 rd Gear 12. 2 nd Gear 13. 1 st 2 nd Speed Synchroniser 14. Mainshaft 39
Countershaft Assembly How to Disassemble the FS-6406 Countershaft Assembly Special Instructions As the individual countershaft gears are pressed from the shaft, make sure to remove the corresponding gear key. Special Tools Bearing pullers Snap ring pliers Press Vice with brass jaws or wood blocks 1. Position countershaft in a vice with the front bearing up. 2. Position puller jaws into the countershaft bearing notches and remove the bearing. 3. Remove the drive gear retaining snap ring. 4. Use drive gear rear face as a base and press drive gear from the countershaft assembly. 5. From the shaft, remove the drive gear locating key and spacer. 40
How to Disassemble the FS-6406 Countershaft Assembly (Continued) 6. Use 5 th gear rear face as a base and press 5 th gear from the countershaft assembly. 7. From the shaft, remove 5 th gear locating key. 8. Use 4 th gear rear face as a base and press 4 th gear from the countershaft assembly. 9. Use 3 rd gear rear face as a base and press 3 rd gear from the countershaft assembly. 10. If damaged, remove the countershaft bearing. 41
How to Assemble the FS-6406 Countershaft Assembly Special Tools Snap ring pliers Press Sleeve type driver 1. With 3 rd gear splined end hub to shaft front, position the gear and shaft in the press. Press 3 rd gear into place. 2. With 4 th gear splined end hub to shaft rear, position the gear and shaft in the press. Press 4 th gear into place. 3. Install 5 th and drive gear keys on the countershaft. 4. With 5 th gear long hub to shaft front, align 5 th gear key-way with shaft key, position the gear and shaft in the press. Press 5 th gear into place. 5. With drive gear long hub to shaft rear, align drive gear key-way with shaft key, position the gear and shaft in the press. Press the drive gear into place. 6. Install drive gear retaining snap ring in countershaft front groove. 42
How to Assemble the FS-6406 Countershaft Assembly (Continued) 7. Using a sleeve type driver or heat lamp and install the front countershaft bearing. 8. Using a sleeve type driver or heat lamp and install the rear countershaft bearing. Use Tool Fl 2513 Final Check Make sure all gears are pressed into place. Make sure the countershaft bearings are installed. How to Install the FS-6406 Reverse Idler Gear Assembly Special Instructions The reverse idler can be assembled in either the ver tical or hor izontal case position. Lubricate the bearings and idler shaft with oil before assembly. 1. Insert the spacer in the reverse idler gear. 2. On either side of the reverse idler spacer, install the bearings. 3. Use grease on the reverse idler thrust washers to hold in place. 4. Position washer tangs to align housing grooves. 5. Install the reverse idler assembly in housing. 6. Insert the idler shaft into the case bore, line up shaft notch with case notch. Do not install the shaft all the way. 7. Install the locating ball. 8. Drive the shaft into position. Final Check Make sure the idler gear rotates freely. 43
How to Install the Countershaft Assembly 1. Carefully lower countershaft into case. 2. Turn transmission case on end. Position countershaft assembly into front bearing race. 3. Install countershaft rear bearing race into case. 4. Temporarily install new shims over countershaft rear bearing cup. 5. Install countershaft rear bearing cover and four capscrews. Tighten capscrews to recommended torque. 6. Rotate countershaft to seat bearings and races. Position dial indicator as shown, lift countershaft to measure end play. 44
How to Install the Countershaft Assembly (Continued) End Play Model FS - 6406 Countershaft End Play 0.15-0.25 mm 7. Add shims for more end play and remove shims for less end play. NOTE: Once end play is correct remove bearing cover and apply a light coat of Loctite 510 to face of retainer and both sides of shims. Coat threads of capscrews with Loctite 262 and re-torque. 8. If fill plug and drain plugs were removed, coat threads of plugs with Loctite 262 and install to proper recommended torque setting. How to Install the Mainshaft Assembly Special Instructions The countershaft must be installed first. Make sure the synchroniser cups on the mainshaft front end stay in position as the mainshaft is lowered into the case. Top of the rear bearing cover is marked for proper installation. Setting end play is done in the vertical position. When setting end play the rear bearing cover, yoke and output shaft nut will be installed, removed, and installed again. After end play is correct, apply a light coat of Eaton/ Fuller sealant Loctite 518 or 515 or equivalent to both sides of the shims, case, and cover before assembly. Special Tools Sling and hoist Flanged driver Dial indicator 45
How to Install the Mainshaft Assembly (Continued) 1. Using a sling around the mainshaft. 2. Carefully lower the mainshaft assembly into the case while guiding the output shaft through the rear case bore. 3. Remove the sling and place synchroniser in neutral. 4. Coat output shaft bearing cover oil seal outer diameter with loctite 518 or equivalent 5. If removed, install the oil seal with flanged driver. 6. If removed, install output shaft bearing race. 7. Temporarily position shims on the rear bearing mounting surface. 8. Position the rear bearing cover over the shims. 9. Install the retaining nuts and tighten to 82-88 Nm of torque. 10. Make sure the mainshaft rotates freely. 46
How to Install the Input Shaft Assembly Special Tools Sleeve type driver (FL2513) Flanged driver 1. Using the proper size sleeve type driver, install the front tapered bearing on the input shaft. (2513) 2. Install the input shaft by aligning the clutching teeth on the 5 th -6 th speed synchroniser and input shaft clutching teeth. 3. Coat the outer diameter of the front bearing cover oil seal with a light coat of Loctite 510. Install the oil seal with a flanged driver. (2363 + 3016 4. Install a new input shaft bearing race in the front bearing cover. (2363 + 3016) 5. Install the front bearing cover and gasket, align the cover and gasket with the six capscrews holes in the case. Install the six capscrews and tighten to the recommended torque. NOTE: The top of the front bearing cover is marked TOP for proper installation. 6. Install the speedometer drive or rotor on the output shaft. 47
Special Instructions Setting end play is done in a vertical position. When setting end play the rear bearing cover, yoke and output shaft nut will be installed, removed, and installed again. After end play is correct, apply a light coat of Loctite 518 or 515 or equivalent to both sides of the shims, case, and cover before assembly. Special Tools : Dial indicator Setting End Play Procedure 1. Place transmission in a vertical position with front end down. 3. Temporarily install the flange and output shaft nut., tighten nut to 645-711 Nm 3. Rotate the output shaft and mainshaft six (6) times clockwise and six (6) times counter-clockwise to seat bearings and races. 4. Position the dial indicator on the output shaft end. 5. Pry up on the output shaft to measure the end play. End play must be set per chart. Model FS-6406 End Play Mainshaft End Play 0.15-0.25 mm 6. End play must be set per table 7. Remove shims for less end play, add shims for more end play. 8. Remove output shaft nut, yoke and rear bearing cover, coat the shims. Position shims and rear bearing cover on case, rear bearing cover top is marked for proper positioning. 9. Install the retaining nuts, tighten to 82 88 Nm of torque. Final Check Make sure nuts are properly torqued. Make sure the output shaft rotates. Make sure end play is within specification. 48