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The transfer case on a evo is a lot different. The first thing is the rs have a 2% overdrive in he rear of the car, Secondly an evo when the transfer case fails it becomes 100% rwd due to the clutching being for the front, that's why it can only put 50% to the front wheels. They are similar in there design style using wet clutches, but ultimately what dies in evo transfer cases is the gears. In the rs put it has only a ring pinion gear then a whole ton of wet clutches, all the shavings are from wet clutches, that's why you replace the fluid every 30k, thanks to the overdrive there is a constant wear.
Uh? Where did you hear that?

The S-AWC system does not fail to RWD if the center diff dies. The center diff is like an open differential with a locking feature that's actively controlled.

During normal operation it sends power wherever it wants, usually to the end with the least traction. However, when the computer system detects wheel slippage and does not desire wheel slippage it will lock the front and rear together, forcing a 50/50 power split.

So, when it fails, it will send power front or rear to the wheels with the least traction like any other diff. The Active portion of it involves locking the center differential so that power is split 50/50 guaranteed.

So, example.

Launching from a dig.

With a broken center diff, the power will be directed to the front wheels as they have less traction when weight transfers rearward. When the center diff is functioning normally the computer will command the center diff to lock, forcing front and rear tires to turn at the same rate. This essentially takes power away from the front wheels and sends it to the rear, creating better acceleration.


If the S-AWC center diff fails, its slightly better than if our RDU fails. With a broken center diff, S-AWC still sends some power rearward, just not a lot of it, and the system gets heavily front biased.

If our RDU fails, well, we become 100% FWD.
 

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Every 30k? Are we talking about the EVO or the RS here? The service manual in this car is piss-poor and just calls for regular oil / filter changes. If for the RS, where is this mentioned?
Read the whole thread, he doesnt know what he's talking about with the RS. The RS has NO clutches in the PTU.

Ciao
 
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