Quick help request - trouble refilling subaru 4eat

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Nov 9, 2004
central Georgia
Did a trans drain and refill on a friend's 2003 subaru forester 4eat automatic.
As I was refilling, fluid started spilling out the drain hole like it was overfilled.
Car now slips in and out of gear.
Every time I check the level (engine running, cycle through all the gears with warm engine) it keeps spitting up fluid like it's overfull.
I'm pretty positive that the roughly same amount of fluid is in there as before now.

Do these cars get air bubbles in them? Any tricks I'm missing?
Right now, I'm just driving the car up on ramps, opening the drain, letting a little out, drive the car again, recheck the level...

This is quite embarrassing as I just did this 2 weeks ago on my Saab without incident and got the level exactly right... ugh!
Yup... that's exactly what I did. The front diff now has 3 quarts of Dex III in it and the trans is 4 quarts low.

As the natives say up here, "OH [censored]".

I'm going to calmly have dinner and then think about what the heck to do now!

Suggestions welcome. Looks like it takes GL-5 80w-90, right? Anyone know what size nut for the front diff while I'm digesting?
I don't kow the size of the nut.

Drain the diff and fill it up with some cheapo fluid. Then drive around for an hour or so. Then drain it again and refill with the fluid you normally use. All the ATF will really do is clean things off some. It shouldn't hurt anything since you caught it. Hopefully the clutches in the tranny aren't damaged.

Oh yea, un't forget to fill the tranny up the rest of the way.
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I doubt I hurt the transmission as I only drove it halfway down the block and back a couple times with a very light foot (less than 15 mph). Thanks for the info.

Off to oreilly's or wallyworld...in my car instead.
so you drained 4 quarts from the transmission two weeks ago. you put the trans fluid in the differential instead of the trans? The transmission has been running 4 quarts low for two weeks and is slipping !?!? This is your friend's transmission? One thing about transmissions, once they start slippping, they will get worse over time. You better be glad your not my friend.
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Oh my. If yours is anything like an '05 Legacy, you need a big honking Torx bit to remove the front differential drain plug. I had to work on one of these once. I want to say it was a T12 or T14 bit, can't remember exactly, but it was BIG. If it hasn't been removed before, you will also need a breaker bar; apparently Subaru really leans on those at the factory. Good luck!
Diff plug came off with a 21 mm socket and short extension.

Cutehumor, I think you misunderstood. I did this about 2 hours ago and the car has been driven a grand total of 1 block!
Originally Posted By: parimento1
may be a stupid question but ru refilling it on the ramps??

Not stupid at all - you're thinking like me. You can't get an accurate reading if the car has to be level while on ramps!
Thanks all for the assistance.

Car is running fine now - smoother than before actually.
Did 2 drain and fills on the front diff with 80w-90. Drove it a bit in between.
Transmission took 4.5 quarts of Dex III.
Oil and filter change done.
Levels were always checked off the ramps.

17mm socket for the oil and trans, 21mm socket for the front diff. It's not hard...so long as you are filling the right orifices with the proper fluids! I don't know how I missed the transmission fill tube...

Now my friend should be all set to tow a small Uhaul trailer back from AZ to WI.
YOu hurt the tranny, and took life out of it. You shortened it's career. How much? Who knows?
This could be serious.
Are you going to tell your friend that you are responsible for this?
OK. You did just fine. Great job.


Addressing the problem you caused IS help. It's the only constructive thing anyone can do for the future of the vehicle.
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