Drive Pinion & Countershaft Gear

Fig. 6 Countergear replacement:

DISASSEMBLY

1. On all except overdrive units:
a. With a dummy shaft, drive countershaft through rear of case and lower countershaft gear to bottom of case.
b. Remove drive pinion bearing retainer attaching bolts, then slide retainer and gasket from pinion shaft. Pry pinion or seal from retainer. Use caution not to nick or scratch seal bore in retainer or the surface on which the seal bottoms.
c. Remove snap ring from outer race of pinion bearing, then with a mallet drive the pinion and bearing assembly into case and remove through case rear.
2. On all units, remove pinion bearing inner snap ring, then press pinion from bearing.
3. Remove snap ring and roller bearings from drive pinion cavity.
4. Remove countershaft gear from bottom of case.
5. Remove dummy shaft, needle bearings, thrust washers and spacer from countershaft gear.

ASSEMBLY

1. Lubricate countershaft gear bore and install roller bearing spacer with dummy shaft into gear. Center the spacer and dummy shaft.
2. Install 19 rollers, a spacer ring, 19 more rollers and spacer ring into gear.
3. Lubricate and install new thrust washers, if needed, on dummy shaft with tang side facing toward case boss.
4. Place countershaft gear assembly on bottom of case.
5. Press drive pinion bearing onto pinion shaft with outer snap ring groove facing front of transmission. Fully seat the bearing against gear shoulder.
6. Install new bearing retaining snap ring.
7. With pinion shaft held in a soft jawed vise, install 16 roller bearings in shaft cavity. Coat bearings with heavy grease and install bearing retaining snap ring in groove.
8. On all except overdrive units:
a. Install drive pinion and bearing assembly through rear of case and position in front bore. Tap into place with a mallet and install outer snap ring in bearing groove.
b. Insert countershaft in bore at rear of case and raise the countershaft gear until the teeth mesh with drive pinion gear. Ensure thrust washers remain properly positioned.
c. Align dummy shaft with case bores, then push countershaft into gear. Tap shaft into case until shaft end is flush with case surface. remove dummy shaft.
9. On all units, install new oil seal in retainer bore.