VW Self-Study Programme 237: Manual gearbox 02T Design and Function

Service.
Self-Study Programme 237
Manual gearbox 02T
Design and Function

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The 02T 5/6-speed manual gearbox
237_010
Gearbox design
With the new 02T 5/6-speed manual gearbox of
The type diversity within the gear and final drive
the MQ200 series, Volkswagen has succeeded
ratios allows an optimum compromise to be
in developing an ultra-light twin-shaft gearbox.
found between sporty and economical gearbox
The housing is manufactured from magnesium.
design for all automotive applications.
The gearbox can transmit up to 200 Nm of
torque and is used throughout the Group in
The gearbox is operated by means of selector
combination with various engines ranging from
cables. The clutch control is hydraulic.
the A00 class to the A class.
The development goals for the new gearbox
The final drive ratios and the ratios of the
were as follows:
individual gears can be matched to the power
outputs of the various engines.
– Easy and exact gear-changes
– Optimal efficiency
– Low weight
– Modular technology
– Standard cable-operated gearbox
New
Important
Note
The Self-Study Programme
Please always refer to the relevant Service Literature
is not a Workshop Manual!
for all inspection, adjustment and repair instructions.
2

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Table of contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Modular system
Gearbox mechanicals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Gearbox design
Input shaft
Output shaft
Bearing support
Double synchronisers
Differential
Force path
Selector mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Outer selector mechanism
Inner gear change mechanism
Selection movement
Shift movement
Reverse gear lock
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6-speed-version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Gearbox design
Modifications to the 5-speed version
Force path
Test your knowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3

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Introduction
The modular system
Clutch release lever
Individual modules are assembled in modular
form.
This increases their functionality after assembly
in series production and in the service workshop.
The modules are:
237_040
Clutch release lever
Selector shaft
This module contains the clutch release lever, the
release bearing and the guide sleeve.
Selector
mechanism cover
Selector shaft with selector mechanism cover
All blocking detent, spring and guide elements of
Angle piece
the selector mechanism, as well as the angle
piece for adjustment of the selector mechanism
are accomodated in this module.
Shift finger
237_041
Inner
selector mechanism
The inner selector module
with shift forks, selector plates and bearing.
Bearing
237_042
support
Input shaft
The bearing support
Output shaft
with the two grooved ball bearings and pre-
assembled powertrain and output shaft.
237_043
4

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The housing
is made from magnesium and consists of 2 parts
In comparison with aluminium, magnesium has a
(gearbox housing, clutch housing).
lower density and therefore also lower strength.
The gearbox housing is sealed off from the
This was compensated for by thicker ribbing and
exterior by a cover.
increased wall thickness.
The fixing points for the left assembly mounting
The result is a mass reduction of 2.5 kg
bracket are located at the top of the gearbox
compared to the conventional aluminium
housing. The attachment points for the self-
construction.
aligning bearing support are located at the
bottom of the gearbox housing.
The lower material density of the
housing necessitates increased
bolt screw-in depths.
To protect the housing against
Fixing points for
electrochemical degradation, the
assembly mounting
bolts are coated (see SSP 192,
page 36/37).
Clutch housing
Gearbox housing
cover
Gearbox housing
237_039
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Gearbox mechanicals
Gearbox design
Reverse idler gear
Gearbox housing cover
The 02T manual gearbox is a compact gearbox
for 5-speed front wheel drive.
It is a twin-shaft gearbox with an additional axle
for reverse gear.
The gears on the input and output shafts are
helical-cut and continously in mesh.
All change gears run in needle bearings to
maximise smoothness.
Gearbox housing
The reverse gear is straight-cut.
The 1st and 2nd gears are engaged on the
output shaft and the 3rd, 4th and 5th gears are
engaged on the input shaft.
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When reverse gear is selected, the reverse idler
gear is engaged on a separate shaft between
the input and output shaft, and the direction of
rotation the output shaft is changed.
All forward gears are synchronised. 1st and 2nd
gears have double synchronisers.
Torque is transmitted to the final drive gear, and
therefore also to the differential, via the output
shaft gear.
Clutch housing
Clutch release lever
Input shaft
Output shaft
Output shaft gear
Differential
Final drive gear
237_004
7

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Gearbox mechanism
The input shaft
is mounted in a bearing assembly in the gearbox
housing together with a cylindrical roller bearing
in the clutch housing (loose bearing) and with a
grooved ball bearing (fixed bearing).
For mass reduction, the input shaft has a deep
bore.
Change gear, 5th gear
237_031
Synchromesh
Change gear, 3rd gear
body, 5th gear
Gearing,
Gearing,
Change gear, 4th gear
1st gear
2nd gear
Deep bore for mass
reduction
237_032
Gearing, reverse
Cylindrical roller bearing
Locking ring
Bearing support
with grooved ball
Synchromesh body, 3rd/4th gear
bearing
The 1st, 2nd and reverse gear wheels are
The synchromesh body of 3rd/4th gear and 5th
connected positively to the input shaft.
gear are connected positively to the input shaft
via a longitudinal grooved spline.
The 3rd, 4th and 5th gear wheels are loose and
run in needle bearings.
After one of the gears is engaged, the
corresponding "idler gear" is also connected to
the input shaft.
Locking rings hold the gears in position.
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The output shaft
has a fixed / idler bearing.
As with the input shaft, the output shaft runs in
bearings in the gearbox housing
– together with a cylindrical roller bearing
(idling) in the clutch housing
– together with a grooved ball bearing (fixed)
which is mounted together with the input shaft
in the bearing assembly.
For mass reduction, the output shaft is hollow-
drilled.
237_033
Change gear, 1st gear
Change gear, 2nd gear
Gear wheel, 5th gear
Gear wheel, 3rd gear Gear wheel, 4th gear
Bore for mass
reduction
237_034
Locking ring
Bearing support with
Final drive gear
grooved ball bearing
Synchromesh body, 1st/2nd gear
Cylindrical roller bearing
The 3rd, 4th and 5th gear wheels and the
The 1st and 2nd gear wheels are idler gears and
synchromesh body for 1st/2nd gear are
run in needle bearings on the output shaft.
positively connected to the output shaft in the
direction of rotation by means of close-spaced
gear teeth.
Locking rings hold the gears in position.
9

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Gearbox mechanism
The bearing support
New
The modular design is a new feature of the
gearbox layout.
A module of this type is the bearing support with
the two grooved ball bearings.
The grooved ball bearings are not mounted
directly in the gearbox housing, they are seated
in a separate bearing support.
237_035
Bearing support
Input shaft
The complete shaft and gear packet of the input
and output shaft is pre-assembled outside the
gearbox housing in the bearing support and,
thus, can easily be installed in the gearbox
housing.
237_036
Output shaft
For repair work, the bearing
support together with the two
grooved ball bearings is replaced
completely.
See also the instructions in the
Workshop Manual.
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