Hi All,

 

I have noticed that on my 92 Loyale, auto, and 4WD that runs and shifts very smoothly.

 

However, the automatic transmission fluid slowly disappears (about 1/3 quart) after a month.

 

I have parked the car on papers overnight but cannot find any leaks!

 

Where's it going?

 

:cornfuzz:

T.J.

As you may know an automatic transmission is a hydraulic system. Being hydraulic, it uses a certain amount of pressure to operate. My bet is it's only leaking under pressure. Depending on how big the leak is, you may be able to get some drips if you have the car running at fast idle, set the parking brake, and put it in 1st gear, then let it sit. If the leak is a very small one this probably won't reveal anything.

 

Check the vacuum line running to the modulator. Is there any fluid in it? If there is, the modulator is bad, and your trans fluid is being sucked into the engine.

 

Check the front diff oil as well. If your front seal is failing, your trans fluid could be going into the diff. Usually it happens the other way around, but it's worth a look anyway.

Also, if your car has a tranny cooler, and of course the lines running to it, check those, the tranny cooler may be damaged or rotting.

Originally posted by subarubrat

Also, if your car has a tranny cooler, and of course the lines running to it, check those, the tranny cooler may be damaged or rotting.

 

Good point... especially since the stock trans cooling lines run to a chamber at the bottom of the radiator on an EA82.

Since I've never had to do any transmission work nor have I looked at it much, I have some questions...

 

Where is the modulator located?

And where dose the vacuum line running to it start from?

Also, is the transmission cooler on the bottom of the radiator?

 

Anything else to look for?

 

Thanks!

 

T.J.

I found where the transmittion fluid was going... it's was slowly leaking into the transfer case.

 

So... I put some transmission stop leak in the AT. It worked! It's been 2 weeks now and I think the leak has stopped.

 

Now the question is...

 

1. Do I drain & refil the transmission with regular fluid?

 

2. Do I drain & refill the transfer case? It's only 2/3 quart over.

 

 

:cornfuzz:

T.J.

Any comments?

Ideas?

 

T.J.

The transfer case? You must mean the front differential.

 

Subarus have no real transfer case per se. The section that the rear drive shaft slips into is actually part of the transmission and has no dipstick to check.

 

Are you saying that the reservoir that you check just behind the engine is getting trans fluid in it? The one with the short thick metal dipstick? That's the front differential.

 

If you're getting trans fluid in there, this transmission will need a rebuild. Stop leak will allow the trans to stay sealed longer, but it will eventually start leaking again. Eventually this leak will destroy the input shaft bearing and the transmission will SEIZE.

 

When it starts leaking again, it's time to consider changing the tranny.

Your right, it's the "front differential" that's taken on a little extra fluid.

 

The short metal dipstick is a little bit beyond it's full mark. So i'm guessing that's where the missing automatic transmission fluid went to.

 

Funny thing is... the car still shifts smoothly and the 4WD drive works great!

 

Can I get by for now by just changing the fluids or should I just leave it alone?

 

Also, what happens if the front differential has too much fluid in it?

 

T.J.

the problem wouldn't be that there is too much oil, it's that it's the wrong kind of oil. If run in the long term you might wear your diff gears out faster. In the short time not a huge deal. If there is too much fluid in there theres more chance it's going to leak out the seals, and your fuel mileage might decrease a bit, because of the extra oil that has to be moved around.

keep an eye on the ATF level, and maybe change the front diff oil ever so often.

 

ither that or spend $$$ to have it fixed, or another auto that is hopefully in good shape.

 

as long as you dont let her run dry. and atf in the diff shouldnt hurt anything, if the leak is slow enough, you can keep it in check. my .02

 

but maybe you can consider a 5spd swap!

Just for grins, I siphoned out some of the extra fluid from the front differential though it's dip-stick tube to bring it back down to normal.

 

I stand corrected... it was only over by 1/5 of a quart.

 

 

T.J.

the only thing is with doing that --is that the front diff is supposed to have gear oil and not atf, which means the gear oil is contaminated. And the final drive gear will wear out quick, you will know this when it will only shift from 1st to 2nd and not into drive.(I realize you said it shifts great right now). Pretty simple to fix--but I've been driving mine like this for almost 3 years now, I bought mine this way w/the gear already stripped and changed it in 2 seconds, so just put the tranny sealer to the automatic and drain the front diff and put 2 and 1/2 quarts of Lucas oil additive. It'll get you by for awhile.

I would strongly recommend draining both and re-filling with the correct fluid - free of "stop leak".

 

Check the level every 600 miles or so, and rebuild if/when it comes back.