Lada Niva 4x4, Service Manual

Page: 34 / 81

Test 2. Accelerate the vehicle approximately up to 100 km/h,
place the gear shift lever in neutral, switch off ignition and let the
vehicle to roll on to a stop; listen to the noise character at various
speeds during deceleration.
ATTENTION. With the ignition switched off, be attentive
and careful. Do not turn the key more than it is necessary, as
it may activate the anti-theft system.
Noise noticed during this test and corresponding to the one
noticed at the first test, does not originate from the final drive
drive gears, as they do not make any noise without load.
And on the contrary, noise marked during the first test and
which was not repeated at the second one, can proceed from the
reduction gears or the driving gear bearing or the differential.
Test 3. On a parked vehicle with the handbrake set, switch
on the engine and, by gradually increasing the revolutions, com-
pare the arisen noises with those noticed in the previous tests.
Noises similar to those indicated in test 1, do not originate from
the reduction gear and are likely to be caused by other units.
Test 4. Noise noticed at the first test and which were not
repeated at the subsequent, originate from the reduction gear; for
confirmation lift the rear wheels, start the engine and engage the
fourth gear. Thus, it is possible to ensure, that noise indeed orig-
inates from the reduction gear, and not from the other units, for
example, suspension or car body.
Reduction gear - removal
If it is necessary to remove only the reduction gear:
- drain oil from the rear axle beam;
- raise the rear part of the vehicle, place it on supports and
remove wheels and brake drums;
- undo nuts fastening the braking plate to the beam and pull
out the axle shafts so that they come out from the differential box;
- disconnect the propeller shaft from the reduction gear, put
a support under the reduction gear casing, turn out the bolts fas-
tening it to the rear axle beam and take out the reduction gear
from the beam, pay attention not to damage the sealing.
Reduction gear - refitting
Before refitting the reduction gear, carefully clean the axle
beam from oil. Place a sealing on the mating surface, fit the reduc-
tion gear into the beam and fix with bolts. Grease the bolt threads
with a sealant. Before greasing the bolts and connections in the
beam carefully degrease all surfaces. Connect the propeller shaft
to the reduction gear. Install the axle shafts and brake drums.
Install a wheel with a tyre and fasten without tightening the
wheel nuts. After refitting both wheels, remove the supports and
lower the vehicle; then tighten the wheel nuts with a torque
wrench.
Fill the axle beam with oil through the filler, previously having
cleaned and screwed in the drain plug.
Reduction gear - dismantle
Fix the reduction gear on a bench. Remove lock plates 9 (see
fig. 3-65), turn out bolts 7 and remove covers 8 of the differential
box bearings, adjusting nuts 10 and outer rings of the roller bear-
ings. Make marks on covers 8 and bearing outer rings, so that to
refit them on former places.
Take out from the reduction gear casing 11 the differential
box together with the driven gear 2 and bearing inner rings.
To remove gear 1 and its components:
- turn the reduction gear casing with the filler neck upward
(fig. 3-66), hold driving gear flange 3 with tool 1, and undo the
flange fastening nut with wrench 2;
- remove the flange and take out the driving gear with the
adjusting ring, rear bearing inner ring with distance sleeve;
- take out the seal, the oil screen and the front bearing inner
ring from the reduction gear casing;
- using tool A.70198 press out the outer rings from the front
and rear bearings;
- remove the distance sleeve from the driving gear and with
the help of a universal puller A.40005/1/7 and tool A. 45008 (fig.
3-67) take out the inner ring from the rear roller bearing;
- remove the driving gear adjusting ring.
To dismantle the differential:
- remove inner rings 2 (fig. 3-68) from the differential box 3
roller bearings with the help of a universal puller A.40005/1/6 and
rest A.45028;
- undo the driven gear fastening bolts and punch out the dif-
ferential pinion shafts from the differential box;
89
Fig. 3-65. Reduction gear:
1 - drive gear; 2 - driven gear; 3 - pinion; 4 - axle shaft gear; 5 - pinion shaft;
6 - differential housing; 7 - bearing cover securing bolts; 8 - bearing cover;
9 - stop plate; 10 - bearing adjusting nut; 11 - reduction gear housing