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Hi Gil. If you mean run in FWD by putting in the FWD fuse, the impression I get from other threads is that it is not recommended. The solenoid that activates when the FWD fuse is in isn't intended for continuous duty and can become damaged. Plus from other threads I've read it really doesn't gain anything in mileage because all the rotating mass and friction is still there.

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Please please PLEASE!!! search before you post a question this broad. It will save us from having multiple threads about the same thing.

 

The answer is no. There is NO benefit to putting in that fuse. It does not save on gas mileage and it does not prevent any wear on the transmission. If anything, it's worse with the FWD fuse than it is normally.

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your all right and all wrong.

 

TB has a few causes. If the plates are all fused together nothing will help. If the plates are gummed up but not fused, it will help, but you need a fluid change.

 

If the internal spool valve is jammed, then it will dump all the pressure to the clutch pack, and delay the inevitable.

 

Then there is the mis matched tires scenario, where it will stop any damage from being done from mismatched tires.

 

Eventully the solenoid will fry, it will take a year or so.

 

The fuse is a stop gap, buying time untill you have the cash to fix the car.

 

 

nipper

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I've been running my '92 Legacy Turbo Touring Wagon LE in mostly FWD for several years now.

1) It DOES help the gas mileage

2) It DOES NOT hurt the transmission

3) I actually like the way it handles in FWD better for the most part. More agile, corners every bit as well as in AWD. (Except for the occasional torque steer :burnout: )

 

I have a switch mounted on the dash that I can flip to make it go from AWD to FWD to AWD at any speed, any time. Bad weather? No problem! Flip the switch! :D

Good weather? Flip it back. ;)

 

The whole thing about "it's gonna hurt a solenoid or this or that" is absolutely trash.

 

Real convenient if I get a flat too.

 

Emily

http://www.ccrengines.com

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I've been running my '92 Legacy Turbo Touring Wagon LE in mostly FWD for several years now.

1) It DOES help the gas mileage

2) It DOES NOT hurt the transmission

3) I actually like the way it handles in FWD better for the most part. More agile, corners every bit as well as in AWD. (Except for the occasional torque steer :burnout: )

 

I have a switch mounted on the dash that I can flip to make it go from AWD to FWD to AWD at any speed, any time. Bad weather? No problem! Flip the switch! :D

Good weather? Flip it back. ;)

 

The whole thing about "it's gonna hurt a solenoid or this or that" is absolutely trash.

 

Real convenient if I get a flat too.

 

Emily

http://www.ccrengines.com

 

 

gee why dont you share your opinion with us :grin:

 

 

i disagree about the solenoid part being trash. It can hurt it, it was designed to cycle on off, not be a constant duty solenoid, but it MAY last for ever that way.

There are enough cases on here about the solenoid failing after being engaged, and not to many with the solenoid lasting a long period of time.

Also if the switch is done on a 96 or newer suabru it will trip a fault code.

 

nipper

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I've been running my '92 Legacy Turbo Touring Wagon LE in mostly FWD for several years now.

1) It DOES help the gas mileage

2) It DOES NOT hurt the transmission

3) I actually like the way it handles in FWD better for the most part. More agile, corners every bit as well as in AWD. (Except for the occasional torque steer :burnout: )

 

I have a switch mounted on the dash that I can flip to make it go from AWD to FWD to AWD at any speed, any time. Bad weather? No problem! Flip the switch! :D

Good weather? Flip it back. ;)

 

The whole thing about "it's gonna hurt a solenoid or this or that" is absolutely trash.

 

Real convenient if I get a flat too.

 

Emily

http://www.ccrengines.com

You are an extreme exception. It clearly states in the owner's manual that you're not to use that fuse except for diagnostic purposes. And, while I agree that there's some rubbish in the manual, that is not.
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Nipper,

 

Yeah, yeah, I know. Opinions are like X#($@s, everybody's got one :grin:

 

Let me add: mine is not the only car that's running like this. I know of at least a dozen others. All of them for several years, and many thousands of miles.

 

Now, Manarius may be right about being pre-96: I'm not positive about that.

On the other hand, SOA also says the EJ25 engines are unrebuildable. (On a big assembly line, I'd have to agree.) But gee, we sell them to dealers all over the country every day.

 

Emily

http://www.ccrengines.com

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I am running my 97 Legacy wagon with the F.W.D. fuse in, and have been for a while with no codes. And I have also been replacing my tires one at a time when they need it for the last ten years and 320,000 miles and Iam still on the same transmission. And I dont care what the manual or experts say.

Nipper,

 

Yeah, yeah, I know. Opinions are like X#($@s, everybody's got one :grin:

 

Let me add: mine is not the only car that's running like this. I know of at least a dozen others. All of them for several years, and many thousands of miles.

 

Now, Manarius may be right about being pre-96: I'm not positive about that.

On the other hand, SOA also says the EJ25 engines are unrebuildable. (On a big assembly line, I'd have to agree.) But gee, we sell them to dealers all over the country every day.

 

Emily

http://www.ccrengines.com

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Nipper,

 

Yeah, yeah, I know. Opinions are like X#($@s, everybody's got one :grin:

 

Let me add: mine is not the only car that's running like this. I know of at least a dozen others. All of them for several years, and many thousands of miles.

 

Now, Manarius may be right about being pre-96: I'm not positive about that.

On the other hand, SOA also says the EJ25 engines are unrebuildable. (On a big assembly line, I'd have to agree.) But gee, we sell them to dealers all over the country every day.

 

Emily

http://www.ccrengines.com

 

i've never seen anyone say an engine is not rebuildable, and i'm an automotive engineer, so i would notice these things. Also there have been more then a few engines here that have been rebuilt at dealers, or torn down so far (ie pistons) that its very close to a rebuild.

 

heheh ild take more comfort if you said you sold a few a week :)

 

nipper

 

nipper

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I don't have a duty soleniod and I've never taken one apart but I have heard from some folks that they run with the fuse in. I have to wonder if whether it works for an extended period with a fuse is it due to condition of the solenoid or quality? Some folks duty solenoids seem to burn out just from regular use.

Maybe its like sensors, you can get a good one that lasts forever or a poor one that fails.

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I don't have a duty soleniod and I've never taken one apart but I have heard from some folks that they run with the fuse in. I have to wonder if whether it works for an extended period with a fuse is it due to condition of the solenoid or quality? Some folks duty solenoids seem to burn out just from regular use.

Maybe its like sensors, you can get a good one that lasts forever or a poor one that fails.

 

cookie you live in SF and you drive a stick? i am impressed.

 

i know its aprils fools right?

 

Duty C solenoid is duty solenoid. The differnce between a duty dolenoid and a solenoid is that a duty solenoid is not desighned to deal with high heat. A regular solenoid can. The duty solenoids in the tranies are blessed in a way. They are in an area where heat is taken away from the, and a cool fluid runs through them. Theri survival depends upon the temperiture. If your driving on blacktop in Az in rush hour you may make it angry, or august in rush hour.

 

 

nipper

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first let me say i don't know anywhere near as much as most of you.

 

0% power to the duty c creates locked 4WD

100% power to the duty c creates FWD

ecu control usually creates 90% front/ 10% rear, and it adjust it as needed.

 

well i don't see the difference between 90% and 100% being so great to garrantee damage to anything. of course i have heard that the duty c works on cycles of electricty, not constant electricty with reduced voltage. and the gamble is $50 duty c, and $300 labor ..... or $900 clutch pack.

 

the duty c in my 97 obw was bad when i bought it with 98k miles. no way to tell why. but since the tires all match and there weren't modifications, i would just say some parts fail sooner than others.

 

this is just my logic and $.02 worth.

 

john

 

Nipper,

 

Yeah, yeah, I know. Opinions are like X#($@s, everybody's got one :grin:

 

Let me add: mine is not the only car that's running like this. I know of at least a dozen others. All of them for several years, and many thousands of miles.

 

Now, Manarius may be right about being pre-96: I'm not positive about that.

On the other hand, SOA also says the EJ25 engines are unrebuildable. (On a big assembly line, I'd have to agree.) But gee, we sell them to dealers all over the country every day.

 

Emily

http://www.ccrengines.com

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first let me say i don't know anywhere near as much as most of you.

 

0% power to the duty c creates locked 4WD

100% power to the duty c creates FWD

ecu control usually creates 90% front/ 10% rear, and it adjust it as needed.

 

well i don't see the difference between 90% and 100% being so great to garrantee damage to anything.

 

john

 

a duty solenoid cycles on and off really fast to vary the torque split. the 90/50 split is varied by doing this. When the solenoid is fully off (failed) you get full awd drive at max internal pressure on the clutches. With the solenoid energized, all the pressure is dumped and you get no rear wheel drive.

By pulsing the solenoid it doesnt really get hot, and it constantly varies the amount of power to the rear wheels.

 

nipper

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i can see where heat cause eletric parts to break down. i wonder if old a/t fluid could casue higher temps and contribute to duty c failure.?

 

a duty solenoid cycles on and off really fast to vary the torque split. the 90/50 split is varied by doing this. When the solenoid is fully off (failed) you get full awd drive at max internal pressure on the clutches. With the solenoid energized, all the pressure is dumped and you get no rear wheel drive.

By pulsing the solenoid it doesnt really get hot, and it constantly varies the amount of power to the rear wheels.

 

nipper

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1) It DOES help the gas mileage
i think this depends on your driving habits. i've done it on more than one occassion for extended periods of time as well (in both manual and auto's). mileage didn't change. i do more highway type driving than stop and go.
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It doesnt really help gas mileage. The same parts are moving no matter what. This is not like some 4wd trucks where the front hubs unlock. On those the unlocking of the hubs disconnect the wheels from the rotational mass of the driveline (which is big and heavy and robs power).

You cant remove the rotational mass on a subaru. The engine has to work just as hard to drive that mass as when it is driven.

 

nipper

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The engine has to work just as hard to drive that mass as when it is driven.
and hey....on a couple of those occassions i actually have removed some of that rotating mass - half of the rear driveshaft, even the rear diff and rear axles too. still no change in gas mileage. the internals of the trans must be the culprit.
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