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Old 02-01-2012, 06:05 AM
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timfitz63 timfitz63 is offline
MT = Doppler Shifting
Location: Lorena & San Antonio, TX
Join Date: Aug 2010
Posts: 928
Mein Auto: 2007 X3 (MT)
Just a reminder...

Before folks start using an indestructible metal gear in the transfer case, they may want to go back and review the portion of this thread where some of us pondered the wisdom of this choice over the original plastic gear (Posts #85-87).

A metal replacement gear will be far more durable, without question, than the original plastic gear; but BMW may have deliberately intended that a plastic gear be used in this application in order to protect the more expensive components (e.g., the actuator motor), should the transfer case system become jammed for some reason: the relatively inexpensive plastic gear becomes what's called the "design failure point" and more expensive components (like the actuator motor) are spared failure/burnout.

Of course, this is all well and good -- if one can obtain the failed component (i.e., the plastic gear) without having to purchase the entire transfer case from BMW...

But the fundamental point I'm trying to make is that, by replacing the plastic gear with a metal one, one needs to realize that they run the risk (however slight) of damaging other components in the transfer case or xDrive system should a situation arise where the plastic gear would have ordinarily failed in order to protect those other components...

X3 w/6-speed & Sport Package:
A sports sedan disguised as an SUV...
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