Four-speed gearbox (longitudinal section)
1 – primary shaft; 2 – bearing cover; 3 – primary shaft seal; 4 – primary shaft bearing; 5 – breather; 6 – intermediate shaft drive pinion; 7 – roller bearing of the front end of the secondary shaft; 8 – crankcase; 9, 14 – sliding clutches of synchronizers of III–IV and I–II gears; 10, 15 – power forks; 11 – synchronizer spring; 12, 13, 16, 19 – driven gears of III, II, I gears and reverse gear, respectively; 17 – secondary shaft intermediate bearing; 18 – stud for connecting the crankcase and rear cover; 20 – gear shift lever; 21 – seal; 22 – secondary shaft; 23 – speedometer drive gear; 24 – secondary shaft seal; 25 – elastic coupling flange; 26 – nut; 27 – mud deflector; 28 – secondary shaft rear bearing; 29 – rear crankcase cover; 30 – intermediate reverse gear; 31 – intermediate shaft reverse gear; 32 – intermediate shaft rear bearing; 33, 35, 36 – leading gears of I, II and III gears respectively; 34 – drain plug; 37 – intermediate shaft; 38 – lower crankcase cover; 39 – intermediate shaft drive driven gear; 40 – front bearing of intermediate shaft; 41 – bolt.
Five-speed gearbox (longitudinal section)
1 – primary shaft; 2 – bearing cover; 3 – primary shaft seal; 4 – primary shaft bearing; 5 – breather; 6 – intermediate shaft drive pinion; 7 – roller bearing of the front end of the secondary shaft; 8 – crankcase; 9, 14 – sliding clutches of synchronizers of III–IV and I–II gears; 10, 15 – power forks; 11 – synchronizer spring; 12, 13, 16, 19 – driven gears of III, II, I gears and reverse gear, respectively; 17 – secondary shaft intermediate bearing; 18 – stud for connecting the crankcase and rear cover; 20 – V gear engagement fork; 21 – gear shift lever; 22 – seal; 23 – V-gear clutch; 24 – driven gear of the 5th gear; 25 – speedometer drive gear; 26 – secondary shaft seal; 27 – elastic coupling flange; 28 – nut; 29 – mud deflector; 30 – secondary shaft rear bearing; 31 – bolt; 32 – intermediate shaft rear bearing; 33 – V-gear drive gear; 34 – intermediate reverse gear; 35 – rear crankcase cover; 36, 38, 40, 41 – drive gears of reverse, I, II and III gears respectively; 37 – intermediate shaft middle bearing; 39 – oil drain plug; 42 – lower crankcase cover; 43 – intermediate shaft; 44 – intermediate shaft drive driven gear; 45 – front bearing of intermediate shaft; 46 – bolt.
Description of the design
The VAZ-2106 models are equipped with a three-shaft, four-speed gearbox. The VAZ-21065-00 and VAZ-21065-01 cars are equipped with five-speed gearboxes, manufactured on the basis of four-speed ones. Both units are interchangeable and most of their parts are the same.
The gearbox consists of a housing and a rear cover, cast from an aluminum alloy and connected by studs with nuts. The housing is closed from below by a stamped steel cover, which is fastened with ten nuts on studs. The primary, secondary and intermediate shafts are mounted inside the housing on rolling bearings. Their helical gears (except reverse gear) have constant engagement. The primary shaft rests with its front end on a bearing installed inside the engine crankshaft and has splines on which the driven clutch disc "sits".
The roller bearing of the secondary shaft is located in the bore of the primary shaft. The intermediate shaft is made in the form of a gear block and is mounted on a double-row ball and cylindrical roller bearing. Reverse gear is engaged by moving the intermediate gear along its axis into engagement with the spur gears of the intermediate and secondary shafts. The reverse gear gears are located inside the rear cover of the crankcase. The 5th gear gears are also located here (in a five-speed gearbox) and the helical gears of the speedometer drive.
Forward gears are engaged by means of clutches with inertial synchronizers. The switching mechanism consists of forks with rods. The engaged gears are fixed by spring-loaded balls entering the holes of the rods. The impossibility of engaging two gears simultaneously is ensured by locking crackers.
The gearbox is filled with transmission oil in the amount of 1.35 liters. Plugs with self-sealing conical threads are used for filling and draining the oil. The drain plug, screwed into the lower cover, has a magnet inside to catch metal products of wear of the gearbox mechanisms. The ends of the primary and secondary shafts are sealed with rubber cuffs.