Iveco Stralis AT/AD. Manual

72766

72767

Figure 59

Figure 60

Figure 61

Figure 62

Figure 63

The bevel pinion mount (1) is supplied as a spare together with
the tapered roller bearings (2 and 3) and the seals (4 and 5).

Using a press and a suitable tube (1) positioned on the inner
ring of the roller bearing (4), fit the mount (2) on the bevel
pinion (3).

49236A

- 2

phase: closing, with tool 99395216 (1) with an angle

of 80 to 90

°.

Heat the bearing (2) to a temperature of 100

°C for approx.

15 min. in an air circulation oven and drive it in with an
appropriate drift.

526249

FITTING THE MOUNT ON THE
BEVEL PINION

49237

Heat the bearing (2) to a temperature of 100

°C for 15 min.

in an air circulation oven and mount it on the bevel pinion
(1).

72768

Heat the bearing (1) to a temperature of 100

°C for 15 min.

in an air circulation oven and mount it on the bevel pinion
(2).
Lock the bearing by notching the bevel pinion at 10
equidistant points as shown in the figure. This should be done
conscientiously with a suitable punch.

The diameter of the impression has to be between
3.40 to 4.10 mm, corresponding to a depth of 0.30
to 0.44 mm respectively, using a load of 4000 kg with
a ball with a 10 mm diameter.

REAR AXLE MS 13-175

TRALIS

AT/AD

Base - January 2003

49239

49240

19416

Figure 64

Figure 65

Figure 66

If the same pinion-crown wheel unit previously removed is
reinstalled, fit the relative adjusting shims (2) and bevel pinion
support with the seal ring (O-ring) (1) to the differential
housing (3). Make sure the lubrication oil slot is properly
aligned.

Before assembling a new pinion-crown wheel unit, it is
mandatory to understand the meaning of the marks stamped
on both pinion and crown wheel, in order to find out the
proper pinion position.

Part number

Tooth play number

Pinion-crown wheel unit coupling number

Adjustment number, to define the thickness of the
shims to be fitted between pinion support and
differential housing (this number is called CP in the
following examples)

Pinion-crown wheel unit date of manufacturing and
testing (month and year)

Pinion-crown wheel unit rated backlash.

Part and tooth play numbers are marked on the pinion
threaded end.
On crown wheels, the same numbers are generally marked
on the front face.
As an alternative, they may be found on the crown wheel
outer diameter.
For any pinion-crown wheel unit, the crown wheel part
number shall always be even (for instance, 36786), whereas
the corresponding pinion part number shall be odd (for
instance, 36787).
The tooth play number (for example, 10-41) means the
pinion features 10 teeth and crown wheel 41, corresponding
to 4.10 : 1 transmission ratio.

Never use pinion-crown wheel units bearing
different numbers.

1,2

1,2,3,4,5,6

Place the transmission fitting flange (1), complete with baffle
(2), and fit it using a suitable beater. The use of a vice is
recommended. Temporarily tighten the lock nut.

REAR AXLE MS 13-175

TRALIS

AT/AD

Example 3:

Original shim thickness

mm 0.70

Crown wheel C.P. + 0.05

- 0.05

Result

mm 0.65

New crown wheel C.P. - 0.05

- 0.05

New shim thickness to be used

mm 0.60

Example 4:

Original shim thickness

mm 0.85

Crown wheel C.P. - 0.10

+ 0.10

Result

mm 0.70

New crown wheel C.P. - 0.15

- 0.15

New shim thickness to be used

mm 0.80

49241

Figure 67

Each crown wheel has an adjustment number specifying the
rated mounting clearance.
Use this number to calculate the thickness of the adjusting
shims to be fitted between pinion support and differential
housing.
This number (for example, C.P. +0.1, or C.P. -0.1 mm), is
stamped on the crown wheel outer diameter.
To calculate the thickness of the adjusting shims to be fitted
between pinion support and differential housing, proceed
as follows:

Measure the thickness of the shims fitted on the
pinion-crown wheel unit to be replaced. Use a
micrometer or gauge and note the measurement.

Read the C.P. stamped on the crown wheel to be
replaced. If positive (+), subtract this number from
the previously taken measurement (see “1”). If the
number represents a negative value (-) add it to the
measurement taken (see “1”).

Note the result.

Read the C.P. stamped on the new crown wheel.
Add or subtract this value (add if +, subtract if -)
to/from the previously taken measurement (see
item “2”).

The obtained value indicates the thickness of the new shims
to be fitted.

Refer to the following examples, covering all possible
combinations.

Examples of calculation

Example 1:

Original shim thickness

mm 0.75

Crown wheel C.P. + 0.05

- 0.05

Result

mm 0.70

New crown wheel C.P. + 0.10

+ 0.10

New shim thickness to be used

mm 0.80

Example 2:

Original shim thickness

mm 0.65

Crown wheel C.P. - 0.05

+ 0.05

Result

mm 0.70

New crown wheel C.P. + 0.15

+ 0.15

New shim thickness to be used

mm 0.85

A number, specifying the rated backlash between pinion and
crown wheel after manufacturing, is stamped on all units.
This number is found on the crown wheel outer diameter.

Insert the screws (2) and tighten to the prescribed torque,
using a torque wrench (1).

- 1

step: tighten using the torque wrench (1) to a torque

of 100 Nm (10 kgm);

- 2

step: tighten the screw (2) using tool 9935216 with

an angle of 60

° ÷ 70°.

The measurement obtained at “2” shall be used to
calculate the thickness of the adjusting shims to be
fitted between pinion support and differential
housing, in relation to the new pinion-crown wheel
unit to be installed.

Spare parts shims, to be fitted between pinion
support and differential housing, are provided with
the following thickness: 0.125 - 0.200 - 0.500 mm.

Reassembling the differential housing

REAR AXLE MS 13-175

TRALIS

AT/AD

Base - January 2003

20670

49225

49244

49245

Figure 68

Figure 69

Figure 70

Figure 71

Figure 72

Turn the unit by 90

°.

Using tool 99370317 (5), lock the flange (3). Using wrench
99355088 (2), multiplier (4) and torque wrench (1), tighten the
pinion lock nut to the prescribed torque (1350 to 1370 Nm).
Place the caps, making sure reference tabs match. Tighten the
screws, complete with washers, to the prescribed torque by
means of a torque wrench.

Then, slightly push the bearing outer rings (1), to make sure
they slide smoothly within their housings.
Remove the screws, complete with washers, and caps.

Position the external rings (3) of the bearings

Using hook 99370509 (1), lift the previously assembled
gearcase (2) and place it onto the differential housing.

Position the caps (2), suitably settle them using a hammer and
insert the screws (3), complete with washers. Tighten the
screws to the prescribed torque, using a torque wrench (1).

Lubricate the conical roller bearings (1), manually tighten the
ring nuts (2) until they touch the external bearing rings;
tighten the screws (3, Figure 71) to the prescribed torque.

49242

Check that the multiplication factor of the multiplier
(4) is correct.

REAR AXLE MS 13-175

TRALIS

AT/AD

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Iveco Stralis AT/AD. Manual - part 145