Fifth Gear Removal
1. Remove mainshaft fifth gear nut as follows:Installing Nut Wrench On Mainshaft Fifth Gear:
a. Install nut wrench on fifth gear nut.
Use Nut Wrench 6443 on standard duty models and Wrench 6743 on heavy duty models.
b. Note that wrench only fits one way on nut. Be sure wrench is fully engaged in nut slots and is not cocked.
c. There are four splined sockets available to retain the mainshaft while removing the fifth gear nut.
- Socket 6441 fits light duty 4X2 mainshaft.
- Socket 6442 fits light duty 4X4 mainshaft.
- Socket 6993 fits heavy duty 4X2 mainshaft.
- Socket 6984 fits heavy duty 4X4 mainshaft.
Remove Mainshaft Fifth Gear Nut:
d. Install breaker bar in appropriate socket wrench.
e. Wedge breaker bar handle against workbench. Purpose of socket wrench and breaker bar is to prevent mainshaft from turning while nut is loosened.
f. Position small end of Nut Wrench 6443 at approximately 10 o'clock position.
g. Strike small end of nut wrench with heavy copper hammer to break nut loose. Nut is secured by interference fit thread plus Loctite adhesive and will require several firm blows to loosen it (nut torque is in 300 ft. lb. range).
h. Once nut is loose, it can be removed by holding nut wrench with breaker bar and rotating output shaft with socket wrench and ratchet.
Mainshaft Fifth Gear Nut Removal:
i. Remove and discard fifth gear nut.
Removing Fifth Gear Shift Fork Roll Pins:
2. Remove roll pins that secure countershaft fifth gear shift fork to shift rail with pin punch. Roll pins are driven out from bottom of fork and not from top.
Removing Countershaft Fifth Gear Clutch Gear Snap Ring:
3. Remove snap ring that secures fifth gear clutch hub and gear on countershaft.
4. Remove fifth gear shift fork and gear assembly Remove assembly by tapping fork off rail with plastic mallet.
5. Remove countershaft fifth gear clutch gear and stop ring.
6. Remove fifth gear shift fork from sleeve.
7. Remove sleeve, struts, and strut springs from countershaft; fifth gear hub, if necessary.
Countershaft Fifth Gear Needle Bearing Removal:
8. Remove countershaft fifth gear needle bearing assembly.
Countershaft Rear Bearing Thrust Washer Removal:
9. Remove cone shaped rear bearing thrust washer from end of countershaft. Note position of washer for assembly reference. Also note that washer bore has notch for locating pin.
10. Remove and retain thrust washer locating pin from countershaft.
11. Remove mainshaft overdrive fifth gear with Puller Tool Set 6444. Note that puller set can be used on both standard and heavy duty transmissions.
12. Gear removal procedure is as follows:
Installing First Puller Jaw On Mainshaft Fifth (Overdrive) Gear:
a. Position first puller jaw on gear. Use Puller Jaws 6459 on standard duty models and Puller Jaws 6820 on heavy duty models.
Seating Puller Flange In First Puller Jaw:
b. Assemble Puller Flange 6444-1 and Puller Rods 6444-3 for 4X2 vehicles, or 6444-4 for 4X4 vehicles.
c. Slide assembled puller flange and rods onto output shaft. Then seat flange in notch of puller jaw.
Installing Retaining Collar Over Puller Jaws:
d. Position second puller jaw (6459 or 6820) on gear and in notch of puller flange.
e. Slide Retaining Collar 6444-8 over puller jaws to hold them in place.
Removing Fifth Gear From Mainshaft Splines:
f. Install Puller and Bolt 6444 on puller rods. Then secure puller to rods with retaining nuts.
g. Tighten puller bolt to remove gear from shaft splines.
Removing Mainshaft Fifth Gear Bearing Plate, Bearing Shims, And Rear Bearing Cup:
13. Remove bolts attaching mainshaft rear bearing plate to gear case and remove fifth gear plate end play shims and bearing cup.