[Brucey]

Changing the Automatic Transmission Fluid (ATF) in the Subaru Outback 4EAT is no harder than changing the standard engine oil. No joke.

Items required:

AT Filter (I got mine at the dealer. While you are there pick up some of the drain plug washers if you do not already have some from changing the oil.)

A socket wrench with a 17mm head.

A drain pan to catch the oil.

The Transmission Fluid. Five quarts should be enough. I use Mobil 1 ATF and can't say if its worth it or not. The transmission uses Dexron III/Mercon fluid. Available at any auto parts store, or even Walmart. Or right here on Amazon: https://amzn.to/2lfFtZp



Step 1: Toss a pan under the transmission pan. It is located about a foot behind your engine oil pan. If you cant change your own oil you might want to leave this to someone else.

Step 2: Unscrew the 17mm bolt on the drain of the transmission pan.

 

[Brucey]

Step 3: While its draining you should notice a small oil filter just above and ahead of the drain plug. Unscrew the filter to drain some extra fluid.

The bolt uses the exact same washer the engine oil drain bolt uses. I also picked up a bunch of these at the dealer. Its not necessary to change it every time.

 

[Brucey]

Step 4: Once the oil is drained (You'll never get every drip out, so don't sweat it.)

Close it up then dab your finger in the Transmission Fluid and rub it around the rubber gasket on the filter. Put the filter back on the transmission (fluid on the rubber helps to make a seal)

It's an identical process to changing the engine oil.

I've also heard of people filling the oil filter which I would agree with except the oil filter is sideways and all it ever accomplishes with me is making a big mess. The oil will make its way into the filter. Some of the other years cars have their filter mounted in the fender vertical. This wouldn't be nearly a mess.

Its very important that you don't start the car during this time. Right now the transmission should have a little over half the recommended amount of fluid, so if you've got the car on ramps wait a minute until you've got some fluid back in.

Also I said that right this method only drains about half of the fluid total out of the transmission. The rest stays in the torque converter but doing this same method two or three times over the period of a few days (or a few hours if you're in a driving mood) should get most of the old fluid out.

Open the hood now and look at the washer fluid reservoir. (its easy to spot)

A little bit above it is the fuel filter and a little inwards and way down underneath some lines is the Transmission Dipstick. Its very hard to find if you don't know what you're looking for, so here is a picture. Its the out of focus yellow circle in the background. See what I mean when I said hard to spot?

 

[Brucey]

This is actually the hardest part. If you dont have a specialty funnel now would be a good time to get creative with paper. (Origami classes might work) I used the funnel in the picture.

 

[Brucey]

The hard part like I said is filling it.

Put the funnel in the dip stick and pour in 4 quarts of transmission fluid. (It took 4 and 1/4th for me to get it just right) You should be good to go now although in a few hours it would be a good idea to recheck the fluid level (Cold or warm either way its hard to get a good reading on it because of the dipstick but since you just poured the fluid DOWN the dipstick to fill the transmission its almost impossible to get a good reading immediately.)

I've also decided at least for me its better to get a cold reading because I have an over sized transmission cooler installed which should effect temps and also should effect the warm dip stick reading.

I used Mobil 1 ATF and I'll report back on how it does with the Subaru 4EAT.

 

[Brucey]

Also here is a picture of it all finished up complete with me spilling/splashing transmission fluid everywhere. To prevent yourself looking like this tin foil will help cover parts you don't want oil on.

This is also a decent picture of the Oil Filter on the automatic transmission.

 

[ivwarrior]

Good write up Brucey. The only thing I have to add is that not all 4EAT trannys have the filter. I forget when they added it, but the older models don't have it. I think it was a late 90's addition.

 

[Brucey]

I believe it was halfway through the 99 year when they added it.
It later got moved somewhere in the car, but not directly attached to the transmission.

All of them also have an internal screen.

 

[Brucey]

I just want to add that from a cold reading, it took exactly 4.25 (4 and 1/4th) quarts of atf to have the dip stick perfectly between the high and the low notches. I've edited the above stuff a bit.

Also, the mobil 1 ATF definately makes shifting smooth, and only half the fluid in at this time is Mobil 1, the other half being generic junk.

 

[Scooby]

9.8qts

Subaru 4eat trans requires 9.8qts ATF.
That is with the torq. conv. drained....

Brucey's method is what I do...only about half , but better than none at all.

Jiffy lube or the dealer can do the full flush with a machine that cycles with a cleaner. Last I checked it was over $200...with synthetic redline ATF.

 

[veeref]

Forgive me if this seems like a stupid question. I have an '06 2.5i AT, and I plan on changing my AT fluids (as well as my F/R diff). Is this guide still pertinent to my model?

Much Thanks,
Randy

 

[nipper]

It takes three drain and fills to get all the fluid out. Drain, fill, start the car and run it through all gears, then repeat. Most the fluid is in the torque converter not the pan.
In the cars without an external filter, there is no need to replace the internal one, as it is just a screen. Most the time this gets replaced and the pan leaks.

nipper

 

[mckeand13]

Without the fancy machine, is it possible to pull the tranny lines (wherever they may be) and put one in a pan and somehow push new fluid in?

 

[Brucey]

If you were to put the out line from the radiator into a big empty contaier, and dip the return line into a massive 10 quart container of fresh fluid, it sounds like it would work. I'm not sure if there would be enough pressure on the return line however.

 

[97obw]

the fluid is lifetime, dont worry about it...makes no difference read your manuals

 

[Brucey]

I guess I don't care what a manual says, but 'lifetime of vehicle' in a factory manual means "till warranty runs out" to me.

 

[rockhopjohn]

Lifetime means to me till you have to carry that load of geologists and gear over a mountain pass in middle of the summer and your tranny fluid gets baked. A little common sense is required when interpreting maintenance interval in the manual.

 

[ivwarrior]

I guess I don't care what a manual says, but 'lifetime of vehicle' in a factory manual means "till warranty runs out" to me.

+1

 

[ETC]

i would have to agree with the majority here. it seems that these "lifetime" parts and fluid are a sales ploy to make you feel better about buying the car. spark plugs don't last 100k miles, i don't care what the box says.

my wifes 740 has "lifetime trans fluid" in it, i asked a very knowledgeable mechanic who specializes in bmws what i need to take care of as far as maintenance since the warranty was up, first thing he said was change the trans fluid around 60k. he knows i'll do it myself so he wasn't trying to make a buck. the fluid for that is bmw specific and costs around $360 just for the fluid, ouch. he basically said "cheap insurance, $500 or so now, $6000 for a new trans later.

chevy recommends a trans fluid/filter change at 60k, people who know these trans say 15-20k.

remember that manual was written on the expertise of the same guys who's solution to a blown headgasket was to add some liquid to the coolant.

 

[mckeand13]

Can somebody ID the tranny lines to the radiator?

Can somebody ID the pressure and return side of the two tranny lines going into the radiator?

Here's my plan:

1) Drain the pan (probably drain about 3qt from what I've read)
2) Refill to appropraite level
3) Remove return line going from radiator to tranny. connect hose to it and run it into a jug.
4) Start car for a short period of time and drain out 1 or 2 qts. (from what I understand, it doesn't come out really fast. Is that true?)
5) Shut car off and refill to appropriate level
6) Repeat until fluid is clear coming from return line.

Anybody have any thoughts on that?

Thanks.