General view of the five-speed gearbox and gear shift mechanism
Gears and shafts of a five-speed gearbox
1 – retaining ring; 2 – reverse intermediate gear axle; 3 – intermediate reverse gear; 4 – primary shaft sealing ring; 5 – bearing; 6 – primary shaft; 7 – bearing retaining ring; 8 – 5th gear drive pinion; 9 – retaining ring; 10 – 2nd gear pinion; 11 – retaining ring; 12 – thrust ring; 13 – 3rd gear pinion; 14 – synchronizer locking ring; 15 – sliding synchronizer clutch; 16 – spring; 17 – synchronizer hub, 18 – block; 19 – 4th gear pinion; 20 – 5th gear pinion; 21 – support plate; 22 – special retaining ring; 23 – oil deflector; 24 – secondary shaft; 25 – 1st gear pinion; 26 – reverse gear; 27 – satellite cage; 28 – axle gear; 29 – satellite axis; 30 – satellite; 31 – differential tapered roller bearing; 32 – speedometer drive pinion; 33 – differential box, 34 – driven gear of the main transmission; 35 – convex special spring washers; 36 – pin; 37 – speedometer drive guide; 38 – driven gear of the speedometer drive
The five-speed gearbox differs from the four-speed gearbox only by the addition of an additional gear and synchronizer, and the use of a modified gear selection mechanism.
Disassembly of a five-speed gearbox is similar to disassembly of a four-speed gearbox (see subsection 8.1.2.3.1) except for the following minor differences.
1. Unscrew the 5th gear lock, remove the spring and locking pin.
2. After unscrewing the bolts and removing the rear cover from the crankcase, unscrew the tie bolt (indicated by the arrow) and disconnect the selection mechanism from the 5th gear engagement lever axis.
3. Remove the 5th gear retaining ring and then the 5th gear gear together with the synchronizer and gear engagement fork.
4. Remove the retaining ring securing the 5th gear pinion to the input shaft and use a puller to remove the pinion from the shaft.
5. Unscrew and remove the 5th gear housing (9 bolts).
6. Remove the retaining rings from the primary and secondary shaft bearings of the gearbox.
7. The subsequent disassembly is the same as for a four-speed gearbox.
Disassembly and assembly of shafts and differential
8. Disassembly and assembly of shafts and differential is the same as for a four-speed gearbox. The only difference is when disassembling the 5th gear synchronizer, in which the locking crackers of the synchronizer hub are secured with a locking plate.