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So I've been playing around with the FWD fuse in my car, because why not. And it's pretty cool, similar to my Brat where you can activate it on the fly. (I ran wires and a switch into the car from the fuse wire and was able to activate it and disengage it while driving)

But I'm very curious as to how it exactly works. The car has an automatic transmission and I understand that the computer engages and disengages a clutch for the rear wheels, and it is the same clutch that controls the power split from front to rear.

But where exactly is this clutch? Is it at the back end of the transmission? Can the disc be changed if they were to wear out? Or do you need a new tranny?


If anyone has a section from a manual or book that explains how it works technically, that would also be appreciated.

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the FWD fuse is interesting.

but if you want real fun,

search for AWD ''locked switch''


it is the reverse of FWD.

it locks the AWD in a 50 / 50 split, front to rear.


not practical in most situations,

but very desirable in some situations.


but it is NOT what you want when driving on dry pavement .


good luck.

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The fwd switch puts power to the duty c solenoid, opening the clutch. In normal driving it pretty much stays open. When the vehicle speed sensors pick up any difference in speed front to rear, it closes and opens the clutch rapidly to send power to the rear.


You can add a switch to shut off the duty c, and have full time 4wd. As johneccleston said DON'T do this on dry pavement. It can shear the center clutch off the shaft. Do a search as to which pin you need to switch on the tcu for this.


Have fun but be warned you can break your trans if you dont play nice with it lol

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+1 install the Duty C switch so you can lock the 4WD in snow/offroad. cutting power to the Duty C gives full transfer pressure to the clutches and "locks" the 4WD.  so you simply need a switch to cut that one wire and re-engage it.


yes the clutch plates are replaceable, though they never really need it.

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