Differential (four-speed gearbox)

PROCEDURE

Differential 1 – bolt; 2 – axle shaft flange; 3 – oil seal; 4 – bushing; 5 – spring; 6 – washer; 7 – spacer ring; 8 – adjusting washer; 9 – tapered roller bearing; 10 – speedometer drive gear; 11 – speedometer drive shaft; 12 – differential case; 13 – final drive ring gear; 14 – cage; 15 – side gear; 16 – round nut; 17 – pinion shaft; 18 – pin; 19 – pinion gear

Differential adjustment 1 – transmission case; 2 – adjusting washer; 3 – tapered roller bearing; 4 – final drive ring gear; 5 – tapered roller bearing; 6 – dial indicator; 7 – plate; 8 – clutch housing; 9 – differential case; 10 – bolt; 11 – gasket

Disassembly. PROCEDURE 1. Press off the inner bearing races 9 from both sides of the differential case 12. 2. Press off the speedometer drive gear 10 (it is practically impossible to remove without destroying it). 3. Drive out the two pins 18 from the pinion shaft 17. 4. Drive out the pinion shaft 17. 5. Remove the side gears 15 together with the round nuts 16. 6. Remove the cage 14. 7. Press the outer bearing races of the differential out of the clutch housing and the transmission case. Caution Removing the final drive ring gear 13 from the differential case 12 requires special tools and specific skills; it is recommended to have this done at a specialized workshop.

Assembly. Caution The outer and inner differential bearing races are not interchangeable and must be replaced as a set.

PROCEDURE 1. Install the cage 14 into the differential case 12. 2. Install the side gears 15 and, holding them by hand, insert the axle shaft flanges 2. 3. Install the two pinion gears 19 into the recesses of the differential case 12 opposite each other, and, rotating the side gears 15, seat the pinion gears 19 in place. 4. Install the round nuts 16 and, holding them, insert the pinion shaft 17. 5. Install the pins 18. 6. Press on a new speedometer drive gear 10. 7. Press on the inner bearing races 9 after heating them to a temperature of 100 °C. 8. Press the outer differential bearing races into the clutch housing and the transmission case. Adjustment. Caution Adjustment is performed after replacing at least one of the following parts: transmission case, clutch housing, differential case, or differential tapered roller bearings.

PROCEDURE 1. Install adjusting shim 2 (see figure Differential Adjustment), 1 mm thick, into transmission case 1 and press in the outer race of tapered roller bearing 3. 2. Press the outer race of tapered roller bearing 5 into clutch housing 8 without the adjusting shim. 3. Install differential case 9 into transmission case 1. 4. Join clutch housing 8 and transmission case 1, installing gasket 11 if equipped. 5. Evenly tighten bolts 10 in a diagonal sequence to torque 25 N·m. 6. Install the ground plate 7. 7. Install dial indicator 6 with 30 mm extension on a universal base. 8. Set dial indicator 6 to zero. 9. Move differential case 9 up and down several times, reading the dial indicator and determining axial play. CAUTION Do not rotate the differential during measurement. Otherwise, the bearings will shift and the measurement results will be incorrect.

10. Calculate the adjusting shim thickness using the formula: S2 = Sn + 0.3 mm, where S2 – calculated thickness of the required adjusting shim, Sn – measured axial play. 11. Remove clutch housing 8 and press out the outer race of bearing 5. 12. Select shims of the required thickness from the kits supplied as spare parts. Available sizes: from 1.45 mm to 2.45 mm in 0.05 mm increments. 13. Install the selected adjusting shims into the clutch housing and press in the outer race of the tapered roller bearing. 14. For further assembly, refer to subsection 5.2.3.