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| VR4 tooth profile comparison |
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| Damage to 1-2 hub |
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| Damaged 1st gear & inputshaft |
W5M33
GSR EVO RVR Front countershaft bearing
failure.
The front countershaft bearing in these
transmissions is normally the one to fail first. When this bearing is
badly worn, it will allow excessive shaft end play, causing damage to the
following components:
-
1st
gear
-
1-2 syncro
hub
-
1-2 selector
fork
And
if driven until the bearing completely collapses the following components
may become damaged:
-
1st gear (damage to
thrust surfaces and gear tooth surface)
-
1-2 syncro hub (damage
to thrust surface)
-
1-2 selector fork (worn
tips)
-
2nd gear (damage to
thrust surfaces and gear tooth surface)
-
3rd gear (damage to
thrust surfaces and gear tooth surface)
-
3-4 syncro hub (damage
to thrust surface)
-
Countershaft (damag e to
thrust surfaces and gear tooth surface)
-
5th gear (driven)
(chipped and broken teeth)
-
-
5th gear cover section
of transmission case (floating shaft causes 5th gear to cut through the
casing)
-
Input shaft (damage to
thrust surfaces and gear tooth surface)
-
Centre diff carrier
(chipped and broken teeth)
-
4th gear (drive)
(damage to gear tooth surface)
-
5th gear (drive)
(chipped and broken teeth and damage to gear tooth
surface)
-
Bellhousing section of
transmission case (countershaft punches through the bearing mount section
of the casing)
In most circumstances where the bearing has
collapsed, due to the high price and the unavailability of replacement
parts the transmission would be considered un-repairable and complete used
transmission must be sourced. Used transmissions for these models can be
expensive and are often not in a very serviceable condition
themselves.
One other option is to install a VR4 gearset into
a 2G type bellhousing.
W5M33 GSR EVO RVR fitted with VR4 gearset.
Advantages:
-
Considerably lower cost
replacement.
-
stronger gear tooth
profiles
-
taller first gear ratio
in most instances (it’s a lucky dip, some of the jap imports will have
same ratio as GSR)
Disadvantages:
-
single syncro rings on
all gears (will not support as high RPM shifts as the dual syncro found on
the higher spec models)
-
not possible to find an
exact match for all ratios on all models.
-
not compatible with
aftermarket upgrade centre differential units.
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| Sandwich plate damage |
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| 5th gear damage |
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| Syncro comparison |
 |
| 5th gear cover |
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