| Make: |
BMW |
| Models: |
E36, E30 M3 |
Transmission Mount Upgrade
A complaint about E36 M3 owners
who explore the limits of their cars at the track and on the street is
the movement of the transmission during turns. In the effort to
create a balance between performance and comfort, BMW specified engine
mounts and transmission mounts which are a compromise to both. BMW
does offer upgraded engine and transmission mounts (referred to as
Groupe N), but they do increase the amount of interior cabin noise
beyond acceptable, as well as costing approximately $1000, not including
installation.
 A
relatively inexpensive alternative to the BMW Motorsport Groupe N parts
is the use of some alternative, factory BMW parts. Upgrading the
transmission mounts is a very easy, effective upgrade which doesn't have
to cost hundreds of dollars. In the picture, you will see a stock
E36 M3 transmission mount on the right, and a stock 320i transmission
mount on the left. Notice how the one on the left is cylindrical
in shape, without the hourglass profile. It's wider profile and
harder rubber does a better job of combating the transmission from
flexing side-to-side. Recent laboratory test show that the 320in mount deflects 24% less (firmer) over a stock E36 M3 tranny
mount. Added with the UUC Motorwerks Tranny Mount Enforcer (found
in the products section), it can make the 320i mount deflect 38% less
than the stock E36 M3 tranny mount without additional cabin
vibration.
 Only
minor modifications must be made to the transmission support brace when
upgrading to the larger, beefier mount. Specifically, the stock
transmission mounts have a 8mm studs at either end. The 320i mount uses 10mm studs. Therefore, the holes where the mounts are
located must be enlarged to accept the new stud size.
Note that there are some
differences between E36 cars and their respective transmissions.
Therefore, please see the chart below for the appropriate, upgraded
mount for your vehicle.
| Model
Year |
Model |
Upgraded Mount |
Retail
Each |
Note |
| '95
to '99 |
M3 |
#23711175424 |
$15.60 |
Need
four (4) M10 nuts. Holes on tranny mount require
enlarging. |
| '92
to '99 |
All
318 |
#23711137817 |
$10.50 |
Hardware
from stock mounts can be used. Tranny mount does not
require modification. Larger mounts will not fit in
transmission mounting location. |
| '88
to '91 |
M3 |
#23711130400 |
$13.30 |
Need
four (4) M10 nuts. Holes on tranny mount require
enlarging. |
Feedback from racers say that
shifting becomes more precise since the transmission is not oscillating
back and forth as much before. A worthwhile upgrade considering a
missed shifted can cause a lot more damage to your engine and your
wallet.
Installing the new transmission
mounts does require accessing the underside of the car, so be sure that
you use appropriate tools and equipment when attempting this upgrade.
Contributed by Bob
Stommel.
|
