REMOVAL & INSTALLATION
1970-86 (521, 620 and 720-D Series)
See Figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 and 15F4W63, F4W71B and FS5W71B
- Disconnect the negative battery cable.
- On 1975-86 models only, remove the shift lever from inside the cab. It is retained to the shaft rail by a C-clip, accessible under the boot. Remove the C-clip and retaining pin, then remove the lever.
- Raise the vehicle and support it with jackstands.
- On 1970-74 models, unscrew the nut securing the bottom of the shifter to the transmission shifting mechanism.
- Disconnect the exhaust pipe from the exhaust manifold. On trucks with a catalytic converter, also remove the exhaust pipe bracket next to the speedometer cable by unscrewing the two mounting bolts.
- Remove the clutch slave cylinder from the transmission case.
- Disconnect the speedometer cable from the transmission extension housing, then disengage the back-up light and transmission switch wires at the switch(es).
- Remove the bracket holding the center bearing of the driveshaft on the third crossmember of the frame.
- Remove the driveshaft(s).
On 4wd models, this requires removal of the transfer case, which should be performed at this time.
- Support the engine with a floor jack located under the oil pan. Place a block of wood between the jack and the oil pan to prevent damage to the oil pan. Support the transmission with a jack.
- Remove the rear engine mount securing bolts and the crossmember mounting bolts. The 1970-71 models (521 series) do not have a removable crossmember; only the rear engine/transmission extension housing mount is removable from the crossmember.
- Remove the starter motor.
- Remove the bolts securing the transmission to the engine, pull the transmission toward the rear until the transmission mainshaft is free of the back of the engine.
- On 1970-71 models, place the rear of the transmission on the crossmember and then pull the transmission down toward the front of the truck and out from under the vehicle.
- On 1972-86 models, separate the transmission from the engine, then lower the transmission out from under the truck.
- Before installing the transmission, clean the mating surfaces of the engine and transmission thoroughly.
- Lightly coat the input shaft splines with grease.
- Reverse the removal procedures. Tighten the engine-to-transmission bolts to 17-20 ft. lbs. (23-27 Nm) for 1970-73 vehicles, 29-36 ft. lbs. (39-49 Nm) for 1974-76 vehicles or to 32-43 ft. lbs. (43-58 Nm) for 1977-86 vehicles.
On the 5-speed transmission, the two bottom bolts are tightened to 7-9 ft. lbs. (9-12 Nm).
- Tighten the crossmember-to-chassis bolts to 20-27 ft. lbs. (27-37 Nm) and the clutch slave cylinder mounting bolts to 18-22 ft. lbs. (24-30 Nm). Be sure to align the marks made earlier on the U-joint and differential flange when installing the driveshaft, to maintain driveline balance.
F4W71C, FS5W71C AND FS5R30A
See Figures 16, 17, 18, 19, 20 and 21
- Disconnect the negative battery cable.
- Disconnect the accelerator linkage if necessary.
- Raise the front of the truck and support it with jack stands.
- Disconnect the exhaust pipe from the manifold and bracket if necessary to gain clearance for transmission removal.
- Tag and disconnect any switches that are connected to the transmission case (back-up, neutral, top gear or overdrive).
- Disconnect the speedometer cable where it attaches to the transmission.
- Remove the driveshaft(s). Don't forget to plug the opening in the rear extension so that oil won't flow out.
- Remove the clutch slave cylinder.
- Remove the rubber boot and console box (if so equipped). Place the shift lever in neutral, remove the E-ring (later models only) and then remove the shifter. On 4wd models remove the transfer case shift lever also.
- Support the engine by placing a jack under the oil pan with a wooden block used between the jack and the pan.
Never position the jack directly under the oil pan drain plug.
- Support the transmission with a transmission jack.
- Loosen the rear engine mount securing nuts temporarily and then remove the crossmember. On 4wd models, remove the torsion bar springs.
- Lower the rear of the engine slightly to allow additional clearance.
- Remove the starter electrical connections and the starter motor.
- Remove the transmission-to-engine mounting bolts, lower the transmission and remove it toward the rear.
Install the transmission in the correct position. Tighten all the transmission-to-engine mounting bolts.
- On Z24i engines, tighten the 4 longest bolts (1 - 65mm and 3 - 60mm) to 29-36 ft. lbs. (39-49 Nm); tighten the 2 shortest bolts (1 - 25mm with nut and 1 - 16mm) to 14-18 ft. lbs. (19-25 Nm).
- On VG30i engines, tighten the 5 longest bolts (1 - 65mm and 4 - 60mm) to 29-36 ft. lbs. (39-49 Nm); tighten the 4 shortest bolts (1 - 55mm, 2 - 30mm and 1 -16mm) to 22-29 ft. lbs. (29-39 Nm).
- On SD25 engines, tighten the 4 longest bolts (1 - 65mm and 3 - 60mm) to 29-36 ft. lbs. (39-49 Nm); tighten the 2 shortest bolts and nuts (2 - 25mm) to 7-9 ft. lbs. (9-12 Nm).
- Install the starter motor and electrical connections.
- Install the crossmember assembly and tighten all retaining nuts to crossmember and rear engine mounts. Install the torsion bars on 4wd models.
- Install the shifter. Install the rubber boot and console box if so equipped.
- Install the clutch slave cylinder.
- Install the driveshaft(s) and connect the speedometer cable.
- Connect any switches that are connected to the transmission case (back-up, neutral, top gear or overdrive).
- Connect the exhaust pipe to the manifold and bracket if necessary.
- Connect the accelerator linkage.
- Connect the negative battery cable. Bleed the clutch hydraulic system if necessary. Road test the vehicle for proper shift pattern operation.
Use these general procedures as a guide for this type of repair. Overhaul of a manual transaxle is a complex and time consuming repair-it is often far better (and easier) to replace the unit with a complete rebuilt assembly.Model F4W63 and Model F4W71B (4 Speeds)
DISASSEMBLY OF THE F4W63
See Figure 22
- Make sure all transmission fluid is fully drained.
- Remove the clutch housing dust cover. Remove the clutch release lever and bearing.
- Remove the front cover retaining bolts and lift out the front cover.
- Remove the bottom cover from the transmission case.
- Unscrew the back-up light switch and the speedometer and remove them.
- Loosen the extension housing-to-transmission case bolts and pull off the housing. It may require a bit of assistance with a rubber mallet.
- Unscrew the check ball plugs and take out the 3 locking springs and 3 check bolts. Be sure you don't lose these.
- Remove the cross shaft and operating lever lock pins by prying off the snaprings. Remove the shafts together with their outer levers and then remove the arm and rod assembly.
When removing the cross shafts, be careful not to damage the lips and grooves of the oil seals with the snapring.
- Mesh the gears in two places, straighten the lockwasher and then loosen the locknut on the mainshaft.
- Drive the countershaft out through the rear of the transmission case and then remove the countershaft along with the countershaft guide. Be careful not to drop the counter gear needle bearings.
Always remove the washers between the counter gear and the transmission case.
- Pry off the reverse idler gear (helical gear) snapring. Remove the reverse idler gear from the shaft, then remove the shaft (with the spur gear) from the transmission case.
- Use a fork rod pin punch and drive out the rod retaining pins. Drive out the fork rods so that the shift forks and fork rod brackets are also removed.
- Remove the mainshaft bearing retainer bolts and then remove the mainshaft assembly from the rear. This might also require the assistance of a rubber mallet; just tap the case a few times.
- Remove the snapring at the front of the mainshaft assembly and then slide off the 3-4 syncro assembly and 3rd gear.
- Remove the mainshaft locknut, lock washer, speedometer drive gear, steel ball, reverse gear and the reverse hub.
- Remove the mainshaft bearing, retainer, thrust washer and 1st gear at the same time with a press. Take out the steel ball, needle roller bearing and the baulk ring. Never apply the press to the 2nd gear.
- Use a press and remove the 1-2 syncro assembly and the 2nd gear.
- Remove the spreader springs and shifting inserts. Separate the coupling sleeve from the syncro hub and then remove the synchromesh assembly.
- Remove the snapring from the front side of the main drive gear bearing and then remove the spacer. Using a bearing puller and a press, remove the main drive gear bearing.
This transmission is constructed in three sections: clutch housing, transmission housing and extension housing. There are no case cover plates. There is a cast iron adapter plate between the transmission and extension housings.
- Remove the clutch housing dust cover. Remove the retaining spring, release bearing sleeve and lever.
- Remove the back-up light/neutral safety switch.
- Unbolt and remove the clutch housing, rapping with a soft hammer if necessary. Remove the gasket, mainshaft bearing shim, and countershaft bearing shim.
- Remove the speedometer pinion sleeve.
- Remove the striker rod pin from the rod. Separate the striker rod from the shift lever bracket.
- Unbolt and remove the rear extension. It may be necessary to rap the housing with a soft hammer.
- Remove the mainshaft bearing snapring.
- Remove the adapter plate and gear assembly from the transmission case.
- Punch out the shift fork retaining pins. Remove the shift rod snaprings. Remove the detent plugs, springs and balls from the adapter plate. Remove the shift rods, being careful not to lose the interlock balls.
- Remove the snapring, speedometer drive gear and locating ball.
- Remove the nut, lockwasher, thrust washer, reverse hub and reverse gear.
- Remove the snapring and countershaft reverse gear. Remove the snapring, reverse idler gear, thrust washer and needle bearing.
- Support the gear assembly while rapping on the rear of the mainshaft with a soft hammer.
- Remove the setscrew from the adapter plate. Remove the shaft nut, spring washer, plain washer and reverse idler shaft.
- Remove the bearing retainer and the mainshaft rear bushing.
- To disassemble the mainshaft (rear section), remove the front snapring, 3-4 synchronizer assembly, 3rd gear and needle bearing. From the rear, remove the thrust washer, locating ball, 1st gear, needle bearing, 1st gear bushing, 1-2 synchronizer assembly, 2nd gear, and needle bearing.
- To disassemble the clutch shaft, remove the snapring and bearing spacer and press off the bearing.
- To disassemble the countershaft, press off the front bearing. Press off the rear bearing, press off the gears and remove the keys.
- Remove the retaining pin, control arm pin and shift control arm from the rear of the extension housing.
- Place the O-ring in the front cover. Install the front cover to the clutch housing with a press. Put in the front cover oil seal.
- Install the rear extension oil seal.
- Assemble the 1-2 and 3-4 synchronizer assemblies. Make sure that the ring gaps are not both on the same side of the unit.
- On the rear end of the mainshaft, install the needle bearing, 2nd gear, baulk ring, 1-2 synchronizer assembly, baulk ring, 1st gear bushing, needle bearing, 1st gear, locating ball and thrust washer.
- Drive or press on the mainshaft rear bearing.
- Install the countershaft rear bearing to the adapter plate. Drive or press the mainshaft rear bearing into the adapter plate until the bearing snapring groove comes through the rear side of the plate. Install the snapring. If it is not tight against the plate, press the bearing back in slightly.
- Insert the countershaft bearing ring between the countershaft rear bearing and bearing retainer. Install the bearing retainer to the adapter plate. Stake both ends of the screws.
- Insert the reverse idler shaft from the rear of the adapter plate. Install the spring washer and plain washer to the idler shaft.
- Place the two keys on the countershaft and oil the shaft lightly. Press on 3rd gear and install a snapring.
- Install the countershaft into its rear bearing.
- From the front of the mainshaft, install the needle bearing, 3rd gear, baulk ring, 3-4 synchronizer assembly and snapring. Snaprings are available in thicknesses from 0.055-0.063 in. (1.4-1.6mm) to adjust gear end-play.
- Press the main drive bearing onto the clutch shaft. Install the main drive gear spacer and a snapring. Snaprings are available in thicknesses from 0.071-0.079 in. (1.8-2.0mm) to adjust gear end-play.
- Insert a key into the countershaft drive gear with 4th gear and drive on the countershaft 4th gear with a drift. The rear end of the countershaft should be held steady while driving on the gear, to prevent rear bearing damage.
- Install the reverse hub, reverse gear, thrust washer, and lock tab on the rear of the mainshaft. Install the shaft nut temporarily.
- Install the needle bearing, reverse idler gear, thrust washer, and snapring.
- Place the countershaft reverse gear and snapring on the rear of the countershaft. Snaprings are available in thicknesses from 0.040-0.060 in. (1.0-1.5mm) to adjust gear end-play.
- Engage both 1st and 2nd gears to lock the shaft.
- On the rear of the mainshaft, install the snapring, locating ball, speedometer drive gear, and snapring. Snaprings are available in thicknesses from 0.043-0.060 in. (1.1-1.5mm).
- Recheck end-play and backlash of all gears.
- Place the reverse shift fork on the reverse gear and install the reverse shift rod. Install the detent ball, spring and plug. Install the fork retaining pin. Place 2 interlock balls between the reverse shift rod and the 3-4 shift rod location. Install the 3-4 gears and rod. Install the detent ball, spring and plug. This plug is shorter than the other two. Install the fork retaining pin. Place 2 interlock balls between the 1-2 shift rod location and the 3-4 shift rod. Install the 1-2 shift fork and rod. Install the detent ball, spring and plug.
- Install the shift rod snaprings.
- Apply sealant sparingly to the adapter plate and transmission housing. Install the transmission housing to the adapter plate and bolt it down temporarily.
- Drive in the countershaft front bearing with a drift. Place the snapring in the mainshaft front bearing.
- Apply sealant sparingly to the adapter plate and extension housing. Align the shift rods in the neutral positions. Position the striker rod to the shift rods and bolt down the extension housing.
- Insert the striker rod pin, connect the rod to the shift lever bracket and install the striker rod pin retaining ring. Replace the shift control arm.
- To select the proper mainshaft bearing shim, first measure the amount the bearing protrudes from the front of the transmission case. Then, measure the depth of the bearing recess in the rear of the clutch housing. Required shim thickness is found by subtracting, the difference is required shim size. Shims are available in thicknesses of 1.4-1.6mm.
- To select the proper countershaft front bearing shim, measure the amount that the bearing is recessed into the transmission case. Shim thickness should equal this measurement. Shims are available in thicknesses from 0.4-1.0mm.
- Apply sealant sparingly to the clutch and transmission housing mating surfaces.
- Replace the clutch operating mechanism.
- Install the shift lever temporarily and check shifting action.
See Figures 23, 24 and 25
This transmission is similar to the F4W71B (4 speed). The overhaul can be accomplished by following the outline for the disassembly and assembly of the 4 speed.
A servo type synchromesh is used, instead of the Borg Warner type in the four speed. Shift linkage and interlock arrangements are the same, except the reverse shift rod also operates fifth gear. Most service procedures are identical to those for the 4 speed unit.
Those unique to the 5 speed follow:DISASSEMBLY
To disassemble the synchronizers, remove the circlip, synchronizer ring, thrust block, brake band, and anchor block. Be careful not to mix parts of the different synchronizer assemblies.
- The synchronizer assemblies for 2nd, 3rd and 4th are identical. When assembling the first gear synchronizer, be sure to install the 0.087 in. (2.2mm) thick brake band at the bottom.
- When assembling the mainshaft, select a 3rd gear synchronizer hub snapring to minimize hub end-play. Snaprings are available in thicknesses of 0.060-0.063 in. (1.50-1.60mm), 0.060-0.061 in. (1.50-1.55mm) and 0.057-0.060 in. (1.45-1.50mm). The synchronizer hub must be installed with the longer boss to the rear.
- When reassembling the gear train, install the mainshaft, countershaft, and gears to the adapter plate. Hold the rear nut and force the front nut against it to a torque of 217 ft. lbs. (294 Nm) for 1977-79 models and 123 ft. lbs. (167 Nm) for 1980 and later models. Select a snapring to minimize end-play of the 5th gear bearing at the rear of the mainshaft. Snaprings are available in thicknesses from 0.043-0.055 in. (1.1-1.4mm).
See Figures 26, 27, 28, 29 and 30
- Remove the control housing, check ball, return spring plug, select check plunger and return springs from the extension housing. Tap the housing lightly with a rubber mallet and remove it from the adapter plate (2wd) or overdrive case (4wd).
- Remove the front cover, oil seal and gasket. Remove the countershaft front bearing shim and the main drive gear ball bearing snapring.
- Tap the transmission case lightly with a rubber mallet and separate the case from the adapter plate.
- Secure the adapter plate in a soft-jawed vise and remove the check ball plugs, check springs and check balls.
- Drive out the fork rod retaining pins. Lift out the fork rods and remove the interlock balls.
- On 4wd models with a mainshaft braking mechanism, remove the lever bracket securing bolt.
- On 4wd models, remove the 3-4 fork rod and then remove the overdrive-reverse fork rod. Rotate the OD-reverse bracket counterclockwise and then remove the fork shaft.
Measure for the proper end-play at all gear assemblies:
- 1st gear: 0.31-0.41mm
- 2nd and 3rd gears: 0.11-0.21mm
- Overdrive (FS5W71C): 0.24-0.41mm
- Turn 2nd and reverse gears until they mesh and then remove the counter front bearing with a suitable puller.
- Remove the sub-gear snapring and then slide the sub-gear bracket, spring and gear off the shaft.
- Remove the counter drive gear along with the main drive gear assembly with a suitable puller. Be careful that the pilot bearing and baulk ring don't fall off.
- Remove the snapring and then slide the 3-4 synchronizer (and 3rd gear) off the shaft.
On the FS5W71C, disassemble the rear of the adapter plate as follows:
- Release the staking and then loosen the countershaft and mainshaft nuts. The mainshaft nut is a lefthand thread.
- Remove the OD counter gear and its bearing with a puller. Remove the reverse counter gear and spacer.
- Remove the snaprings from the reverse idler shaft and then slide off the reverse idler gear, thrust washers and bearing.
- On 2wd models, remove the snapring and slide the overdrive mainshaft bearing and snapring off the shaft.
- Remove the mainshaft nut. Remember, it's a lefthand thread.
- On 2wd models, remove the speedometer drive gear and and steel ball.
- Remove the thrust washer, steel roller, roller bearing and washer.
- Remove the OD main gear, needle bearing and baulk ring. Remove the OD coupling sleeve, shifting inserts and insert springs.
- Tap the rear of the counter gear with a rubber mallet and remove it.
- Press out the OD gear bushing, insert retainer and the OD synchronizer hub.
On the F4W71C, disassemble the rear of the adaptor plate as follows:
- Remove the snaprings, the speedometer drive gear and the steel ball.
- Release the staking on the mainshaft nut and loosen it. Remove the mainshaft nut and slide off the reverse main gear.The mainshaft nut usually has lefthand threads.
- Remove the snapring at the rear of the countershaft and then remove the reverse counter gear.
- Remove the reverse idler gear.
- Tap the rear of the counter gear with a rubber mallet and slide it off the shaft.
- Tap the rear of the mainshaft assembly with a rubber mallet and slide the assembly out of the adapter plate.
- Remove the thrust washer, steel ball and the 1st main gear with needle bearing.
- Press the 1st mainshaft bushing together with the 2nd main gear using a suitable tool, then remove the 2nd gear needle bushing.
- Remove the main drive gear bearing snapring and washer and then slide off the bearing.
- Install all bearings into the case components.
- Install the oil gutter on the adapter plate so that it is expanded on the rear side. Insert the reverse shaft and then install the bearing retainer. Tighten each screw and then stake at two points.
- Press in the main drive gear bearing and install the spacer. Install a snapring so that the clearance of the groove is 0-0.006 in. (0-0.14mm). Snaprings come in sizes from 0.068-0.082 in. (1.73mm-2.08mm).
- Assemble the synchronizers.
- Assemble the 2nd main gear, needle bearing and the 1-2 syncro assembly, then press the 1st gear bushing onto the mainshaft.
- Coat the steel ball and thrust washer with grease, then install them and the 1st main gear to the mainshaft.
- Install the counter rear bearing to the adapter plate.
- Press the mainshaft assembly and the counter gear into the adapter plate.
- Install the 3rd main gear and the 3-4 syncro assembly. Install the synchro assembly.
- Install the mainshaft thrust washer and secure it with the proper size snapring. There should be minimal clearance in the groove.
- Coat the pilot bearing with gear oil and install it on the mainshaft.
- Press the counter drive gear (along with the main drive gear) onto the shaft.
- Install the sub-gear and bracket on the counter drive gear and install a snapring that will minimize groove clearance. Snaprings come in 3 sizes; 0.055 in (1.4mm), 0.059 in (1.5mm) and 0.063 in. (1.6mm). Remove the snapring, sub-gear bracket and sub-gear from the counter gear, then reinstall them with the sub-gear spring between them.
- Install the front bearing onto the counter gear.
- Assemble the parts at the rear of the adapter plate.
- Make sure that the 2nd and reverse gears are meshed and then tighten the locknut. On the FS5W71C, install a new countershaft locknut and tighten it. Stake both nuts with a punch.
- Measure the gear end-play.
- Install the shift rods, interlock plunger, interlock balls and check balls.
- On 4wd models, rotate the OD-reverse bracket clockwise and install the fork shaft. Install the E-ring on the fork rod and then install the lever bracket bolt.
- Coat the lip of a new oil seal with grease and install it in the front cover.
- Apply sealant to the transmission case mating surface and then slide the gear assembly onto the adapter plate.
- Apply sealant to the adapter plate mating surface and then install the extension housing. Install the main drive bearing snapring.
- Install a counter front bearing shim. Install a new gasket and the front cover.
- Install the return spring plugs, check ball, return springs and check plunger.
- Install the control housing with a new gasket.
See Figures 31, 32, 33 and 34
- Remove the check ball plug, check spring and check ball. Remove the interlock stopper. Don't let the check ball fall into the transmission case.
- Remove the control housing, return spring and check ball.
- Drive out the striking arm retaining pin with a punch.
- Tap the extension housing (or OD case) lightly with a rubber mallet and remove it along with the striking arm.
- Remove the front cover and its gasket.
- Remove the stopper ring and the main drive bearing snapring.
- Tap the transmission case lightly with a rubber mallet and remove it. Remove the front cover oil seal.
- Mount the adapter plate in a soft-jawed vise, then remove the OD and reverse fork rod.
- Drive the striking lever retaining pin out with a punch. While pulling out the striking rod, remove the lever and interlock. Then, remove 1-2,3-4 gears along with the reverse shift fork.
- Drive the OD shift fork retaining pin out with a punch, then pull out the OD fork.
- Measure the end-play at each gear. It should be 0.009-0.013 in. (0.23-0.33mm) at all gears except reverse which should be 0.013-0.017 in. (0.33-0.43mm).
- Remove the reverse coupling sleeve. Remove the snaprings from the rear of the mainshaft and counter gear.
- Remove the C-ring holder and then the C-rings on the mainshaft. Use a hammer and punch.
- Remove the mainshaft rear bearing on 2wd models.
- Remove the reverse main gear along with the mainshaft spacer and the reverse synchronizer hub. Remove the reverse gear needle bearings.
- Remove the reverse counter gear. Remove the OD coupling sleeve along with the OD and reverse baulk rings and the spring inserts.
- Remove the reverse gear bushing. Remove the OD counter gear along with the reverse cone.
- Press out the mainshaft and counter gear alternately .
- From the mainshaft, remove the 1st gear washer and steel ball, 1st main gear and needle bearing. Remove the 2nd main gear along with the 1st gear bushing and the 1-2 syncro assembly. Remove the front snapring. Press out the 3rd main gear along with the 3-4 syncro assembly and the 3rd gear needle bearing.
- From the counter gear, remove the rear thrust bearing and the sub-gear components.
- Remove the main drive gear snapring and washer and the remove the bearing itself.
- Install all bearing into the case components. Install the main drive gear bearing and snapring so that the groove clearance is 0-0.004 in. (0-0.1mm). Snaprings come in sizes ranging from 0.074-0.086 in. (1.89mm to 2.19mm).
- Install the components on the counter gear. Remember to tap the sub-gear snapring into place on the counter gear.
- Assemble the 1-2 and 3-4 synchronizers. Install the 3-4 syncro assembly together with the 3rd main gear and needle bearing onto the mainshaft.
- Press the 1-2 syncro assembly along with the 2nd main gear and needle bearing onto the mainshaft.
- Press the 1st gear bushing and washer, the 1st main gear and needle bearing, the steel ball and the 1st gear washer onto the mainshaft.
- Install the counter gear along with the sub-gear components and the thrust washers onto the adapter plate. Remove the counter gear front bearing shim from the transmission case and then position the counter gear assembly into the inverted transmission case.
- Secure the adapter plate to the case with 2 bolts and install a dial indicator on the rear end of the counter gear. Move the gear up and down while measuring the deflection. end-play should be 0.004-0.010 in. (0.10-0.25mm). Select the proper shim.
- Install the reverse idler gear, reverse idler needle bearings, reverse idler thrust washers and the reverse idler shaft to the extension housing (or OD case). Install a dial indicator on the front end of the shaft. Install a straightedge across the extension housing (or OD case) flange as a stopper and then move the shaft up and down to measure end-play. It should be 0.012-0.021 in. (0.30-0.53mm). Adjustment is made by changing the thrust washer; there are 2 sizes: 0.078-0.081 in. (1.97mm and 2.07mm).
- Install the mainshaft and counter gear on the adapter plate and then install the main drive gear on the mainshaft.
- Install the rear side components on the mainshaft and counter gear.
- Install the OD fork rod and shift fork, then press the retaining pin into the shift fork with a punch.
- Install the 1-2, 3-4 and reverse shift forks onto the coupling sleeve.
- Install the striking rod into the shift fork, striking lever and interlock hole and then press the retaining pin into the striking lever. Check for smooth movement of the lever.
- Coat the lip of a new oil seal with grease and install it in the front cover.
- Coat the selected counter gear front bearing shim with grease and install it in the transmission case.
- Apply sealant to the case mating surface and install the gear assembly.
- Coat the check ball with grease and then install it along with the check spring into the interlock stopper.
- Install the interlock stopper assembly and then tighten the check ball plug. Be sure to coat the threads of the plug with sealant.
- Install the stopper ring and the main drive bearing snapring.
- Install the front cover with a new gasket. Apply sealant to the threads of the 3 lower bolts.
- Install the extension housing (or OD case) along with the striking arm. Install the striking arm retaining pin with a punch.
- Install the return spring and check ball and then install the control housing.
- Tighten the control housing bolts to 12-15 ft. lbs. (16-21 Nm).