MAINSHAFT REMOVAL & DISASSEMBLY:
12. Use two pry bars to slide mainshaft and gear
assembly (B-1 through B-22) toward rear of case as far
1. Lock auxiliary transmission in two gears by
as possible. This should slide mainshaft rear bearing (B-
engaging underdrive clutch collar (B-16) with mainshaft
22) out of case far enough to use a puller that clamps on
gear (B-18) and direct and overdrive clutch collar (B-6)
the snap ring of the bearing. Remove rear bearing (B-
with overdrive gear (B-7).
22) and thrust washer (B-21) from mainshaft.
2. Use 2Y " socket to remove drive gear and
13. Pull mainshaft out through rear bearing bore,
mainshaft companion flange or end yoke nuts (A-5 and
lifting the parts from the mainshaft and out the top
B-28) and flat washers (A-4 and B-27).
opening of case as they pull free:
3. Use puller or equivalent and remove main drive
A. Inner race of drive gear pocket bearing (A-
gear and mainshaft rear companion flanges or end yokes
10). This is a two piece bearing. The inner
(A-2 and B-25).
race will usually stay with the mainshaft,
however, the inner race is a slip fit on the
4. Remove front transmission hanger (if used) from
mainshaft and may come off with the drive
drive gear bearing cap (F-7).
5. Remove cap screws (F-4), lock washers (F-6)
B. Direct and overdrive clutch gear and collar
and separate front bearing cap (F-1) from main drive
(B-5 and B-6).
gear bearing cap (F-7). Remove bearing cap gasket (F-
3). Remove front bearing cap oil seal (F-2).
C. Overdrive gear (B-7) with sleeve (B-10),
needle bearings (B-8), and spacer (B-9).
6. Remove cap screws (F-9), lock washers (F-10)
from drive gear bearing cap (F-7). Use pull screws on
D. Underdrive gear (B-12) with remaining
bearing cap (F-7) to separate cap and bearing (A-7) from
caged-or loose needles (B-14), for models
drive gear (A-1).
R8031-P and Q. Model R8031-R unit (B-
12A) gear will be located next to back of
7. After drive gear bearing cap (F-7) has been
case. This gear is a deep reduction gear
removed, tap bearing (A-7) free of bearing cap by
tapping on outer race of bearing from inside of bearing
E. Shift collar (B-16).
8. Remove retaining cap screws (H-6 and J-3) with
copper washers (H-10 and J-4) from mainshaft and
14. Loose or caged needle roller bearings (B-8) are
countershaft rear bearing caps (H-2 and J-1). Separate
also used with mainshaft overdrive gear (B-7). If these
bearing caps from gaskets and case. Check and remove
bearings are to be reused then use caution to prevent
speedometer bushing (H-3) if it is to be replaced by
loss of needles as gear (B-7) is removed from sleeve (B-
removing mounting parts (H-21 through H-25).
9. Remove speedometer drive gear (or spacer if
15. Slide drive gear (A-1) rearward and lift out
used) (B-24) and bearing thrust washer (B-23) from rear
through top opening of case. Remove inner race of
bearing (A-9) from drive gear.
10. To remove mainshaft rear bearing, slide main
16. Use soft hammer and tap outer race of drive
drive gear (A-1) and bearing (A-9) as far forward as
gear roller bearing (A-9) out of front bearing bore of case.
possible. Tap mainshaft (B-1) forward to start rear
bearing off mainshaft and expose retaining lock ring (B-
17. Remove pocket bearing (A-10) from drive gear
2) by using tubular driver against splined shoulder to rear
Caution: Do not drive against threaded section at end
of shaft. Tap shaft forward until mainshaft clutch gear (B-
1. With pry bar on front face of gear (C-6), force
5) bottoms against drive gear (A-1).
countershaft assembly rearward to clear front bearing (C-
2) of which the outer race will remain in case bore. Rear
11. Use screw driver lip in groove of retaining ring to
bearing (C-14) will be pushed out of case remaining on
remove from groove of mainshaft, or use two screw
driver ends on the ends of ring. Push on end and allow
ring to fall in bottom of case.