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Posted: Wed Apr 11, 2007 3:45 pm
by IronMonkeyL255
The 4EAT uses clutch packs actuated by a solenoid to transfer power.

Not sure, but I would think if you did it for too long, you would fry the clutch packs.

Posted: Thu Apr 12, 2007 3:23 am
by 555BCTurbo
Yes, if the 4eat is towed improperly, it will burn out the clutches. That is the reason that the automatic cars have the "front wheel drive fuse" in the engine compartment, which disengages the center differential clutch packs, and therefore makes the car front wheel drive.

Posted: Thu Apr 12, 2007 5:15 am
by jpimm2002
555BCTurbo wrote:Yes, if the 4eat is towed improperly, it will burn out the clutches. That is the reason that the automatic cars have the "front wheel drive fuse" in the engine compartment, which disengages the center differential clutch packs, and therefore makes the car front wheel drive.
I am pretty sure on the 4eat's that the rear wheels aren't hooked up at all unless the solenoid engages the clutchpack. I say this because in the process of towing a 4eat subaru out of a ditch the rear wheels were completely free spinning (engine not running and transmission in park). I think the fuse just signals the TCU not to engage the rear wheels. There is still the danger of towing an automatic with the wheels on the ground, but I don't think the clutch packs themselves are in any danger. With a manual transmission on the other hand you would absolutely destroy things with the speed difference(not to mention it would be like having the brakes on).

Jeremy

Posted: Thu Apr 12, 2007 5:27 am
by 555BCTurbo
You could be right Jeremy...one thing to consider with automatics in general is that they get killed by lack of lubrication...which is not happening unless the pumps are running, which doesn't happen unless the engine is running...

It has been my impression that the clutches stay engaged until acted upon by the fwd fuse, because the STi uses essentially the same setup, and they stay engaged at all times, afaik.

Posted: Thu Apr 12, 2007 6:01 am
by lunes
I was curious about that, and when I tested my car (the 1990 4eat) jacking up the whole car (with the engine off and the trans in neutral, no key in the ignition, no fuse in the "fwd" socket) rolling the rear wheels didn't affect the front, and rolling the front didn't affect the rear, until I turned the key to "run", and THEN the front and back were connected, so it must be disengaged when theres no power, and engaged when on... I don't get the difference between the manual and automatic though. my 4eat is almost perfect balance between front and rear when I try to slide it on gravel, but the 5mt acts as if it is rear wheel preference, is that unusual?


555BCTurbo wrote:You could be right Jeremy...one thing to consider with automatics in general is that they get killed by lack of lubrication...which is not happening unless the pumps are running, which doesn't happen unless the engine is running...

It has been my impression that the clutches stay engaged until acted upon by the fwd fuse, because the STi uses essentially the same setup, and they stay engaged at all times, afaik.

Posted: Thu Apr 12, 2007 6:37 am
by 555BCTurbo
No, your results are not uncommon, my 5mt SS acts very rear happy on gravel too...