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So I cannot get a definitive answer on this...
When my car is up in the air with all 4s, and i put the car in D, the back axles do not spin with the front.
With the car off, the DS spins relatively easily by hand and that spins the rear axle no problem... 

Ive heard that the Autos dont engage the AWD at all times like the Manuals do, and im really only going to notice it during adverse conditions (rain, snow, ice) or hard turning?
Can i get some clarification on this, and do i need to investigating a possible Duty C or Center Diff issue?

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there are some videos of Subarus on rollers or roller equipped ramps that can demo the function. With no load (other than internal friction) you can't get a good idea of how the AWD functions. And, it can make a difference if you have rear LSD or not.

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should be the regular open on mine (the side with no load spins)... and its a 90/10 split.

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there is nothing wrong with your car. it is doing exactly what it is supposed to be doing. If you were to increase rpms a little with it up in the air, the rears would most likely kick in.

if you get binding while doing tight circles, then worry about the duty c.

Otherwise, drive it, enjoy it. I miss my 95 Lifted Lego, but i do like the Foz, too

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Good to know.

I get no binding in tight turns, and sometimes i take them a bit more spirited for the fun of it. I guess when i actually notice something during all weather driving and tight turns and ill consider it an issue. Until then ill stop worrying. Thanks.

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1 hour ago, heartless said:

if this is your first AWD Subaru, you will love it come winter time. :D

 

if it has tires for the job!

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i got all season with about a half a penny of tread or more, ive already taken it through some nasty thunderstorms through north texas a month or so back, there was like an inch or so of standing water on the freeway, raining so so hard, and i was probably one of the only cars managing to go above 50...
it was just recently i had it on stands though, tryin to diagnose a few things and i noticed only the front wheels engage in any gear.

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You can pop a fuse in the FWD socket by the front passenger strut tower. This will show you the difference, too....It's not recommended to drive around in FWD mode for miles and miles (although some do)  and it doesn't help w/MPG either. 

Edited by wtdash
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6 hours ago, Jadu108 said:

it was just recently i had it on stands though, tryin to diagnose a few things and i noticed only the front wheels engage in any gear.

Did you have the hand brake off too? 

I’m not familiar with autos and awd, but dont they use trans fluid pressure to apply drive to the rear end? 

Cheers 

Bennie

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4 hours ago, el_freddo said:

Did you have the hand brake off too? 

I’m not familiar with autos and awd, but dont they use trans fluid pressure to apply drive to the rear end? 

Cheers 

Bennie

handbrake was first thing i checked...
honestly i have no idea, ive just heard mixed things about how the auto awd works, but mostly it seems it does work differently from the manual... Personally it IS indeed my first AWD subaru, i had a FWD 94 impreza before, and ive worked on plenty of others, just never with the trans and awd system. 
Ive heard some say the rears wont engage in the air, and its only when car detects that it needs it through the trans does it engage, and ive heard other ppl say it should regardless at least a little bit :\. IDK...
Honestly ive noticed no change in the cars behavior since the texas thunderstorm, and if anything my gas mileage is a bit better since i recently did bearings, axles, and struts. I was 24 to 25 before hwy, now 25 to 26 hwy. 
Its just something that intrigued me when i noticed it and theres not a lot of clear info on the auto awd... 

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13 hours ago, el_freddo said:

I’m not familiar with autos and awd, but dont they use trans fluid pressure to apply drive to the rear end? 

Cheers 

Bennie

Yes, they use transmission fluid to apply pressure to the clutch packs that transfer power to the rear.

On 7/9/2019 at 12:34 PM, Jadu108 said:

So I cannot get a definitive answer on this...
When my car is up in the air with all 4s, and i put the car in D, the back axles do not spin with the front.
With the car off, the DS spins relatively easily by hand and that spins the rear axle no problem... 

Ive heard that the Autos dont engage the AWD at all times like the Manuals do, and im really only going to notice it during adverse conditions (rain, snow, ice) or hard turning?
Can i get some clarification on this, and do i need to investigating a possible Duty C or Center Diff issue?

As mentioned, it relies on hydraulic pressure to engage the rear axle, so with the car off, driveshaft spinning by hand is definitely fine.

 

Grain of salt, I haven't tested this, nor do I have a car with that AWD that I could test it on.

 

BUT. There are 2 speed sensors, effectively measuring front and rear output speed, when a difference is detected it should feather the clutch packs to send a little torque to the rear. IIRC, regardless of any other conditions, it should apply some pressure to those clutches, which should spin the rear axle with no load on it.

 

The only variable here that I'm unsure of, is that when you have it on jack stands, you're presumably at idle. It's possible that with no throttle detected, it won't apply enough pressure to the clutch packs to spin. If you blip the throttle with it in gear, and they still don't spin, you definitely have a problem.

 

 

 

Also, this information covers nearly all 4EAT AWD Subarus (definitely your '95 Legacy), there are a few exceptions that have VTD AWD with a 4EAT. SVXs in other markets, Outback H6 VDC models (this is what I have, which is why I can't test this), and WRXs, maybe others. These models have a true differential, which is also limited by clutch packs.

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So Ive followed the recommended reading, and it appears i should have had all 4 tires spinning, especially when i switched to 1st gear and blipped throttle, because when the shifter is in 1, the ecu automatically ups the hydraulic pressure to send more torque and power to the rear. Perhaps i misunderstood something in the reading, but what im getting is my MPT is staying disengaged...

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dont "blip" the throttle - bring the rpms up gradually to around 1500-2000rpm and hold it.

also make sure rear brakes are not dragging at all, and check that tranny fluid is at the appropriate level before you do this.

tranny fluid should be checked with the car fully warmed up, idling and parked on level ground.

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18 hours ago, Jadu108 said:

So Ive followed the recommended reading, and it appears i should have had all 4 tires spinning, especially when i switched to 1st gear and blipped throttle, because when the shifter is in 1, the ecu automatically ups the hydraulic pressure to send more torque and power to the rear. Perhaps i misunderstood something in the reading, but what im getting is my MPT is staying disengaged...

It changes the allowable percentage in speed difference front to rear. Similar effect, just slightly different reason

14 hours ago, heartless said:

dont "blip" the throttle - bring the rpms up gradually to around 1500-2000rpm and hold it.

I disagree. The AWD actuation is effected most by the throttle position, gently bringing it off idle may not be enough to change it much. I'd give it a stab of throttle and rev it out to 3-4k and then let off.

 

The best test is in the snow or mud, where there's enough drag so you can sustain 1/2-3/4 throttle and keep the tires spinning. But that's not exactly a practical test. :P

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put the front tires on wet grass or soapy water, or, 2 creepers???, and see if the rear will push the car forward.

Edited by 1 Lucky Texan

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i guess another thing i could do is jack up the front just enough to remove most the pressure on the front, and see if the back moves me forward :/  seems kinda dumb to do, but i dont think im gonna have much wet grass soon (i dont think my people want me to tear up the yard).
what would i do with soapy water, my driveway is pretty course, so im not sure that would work?

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without building some type of roller pads like in youtube videos --- just brainstorming some kind of test.

be safe if you try something that is gonna limit steering/braking ability!

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of course!!! Especially because here in Eugene we dont have the widest roads, or longest driveways :(, not like where i was in Florida :P.
I think IF i decided to do that, I would maybe just let the gas off just enough until I could feel the car start to push, or i would not feel anything and the AWD doesnt work...
I would also maybe do it along the curb, or the nearby HS parking lot which is mostly empty for the rest of the summer now 

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1 hour ago, 1 Lucky Texan said:

drop the front tires onto 2 bags of ice?

using a floor jack is frightening to me, what if it flipped or you drove off the pad?

 

noted.
you think the bags of ice will remove enough traction?

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well, even mud and wet streets have 'some' traction....just spitballin'

try comparing with and without the FWD fuse in.  Compare forward and reverse? maybe get a coupla helpers to video from each side to see what's spinning and what isn't?

maybe spring for more ice ? lol!

 

I dunno

 

 

find a spot to do this without 'high centering' ? ;

 

Edited by 1 Lucky Texan

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