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Discussion Starter #1
Anyone pump out the fluid from a TR690 (the CVT on the 3.6R or WRX) to do a complete flush? I'm thinking the transmission cooler at the front is a good spot at the same time not a fan if air becomes trapped in there forever (thinking unlikely). I wish the service manual would label which one is which. Looks like I have to trace it which is super lame. Included some pictures.
 

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'17 OB 3.6 , '11 OB 2.5 , '11 Legacy 2.5
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I have a 2017 3.6R just like you.

I had mine done at the Dealer. You are very brave :)

Thanks for posting, let us know how it goes.
 

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Brucey
'17 3.6
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I did a drain and fill at 50k. Was as easy as an oil change. Just a couple procedures to watch for when filling.
 

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Discussion Starter #4
You think a temp gun on the cvt fluid pan will be close to the scan gauge? I was looking around the forums and people were saying the pan would be about 3-4F cooler than the CVTF. Don't have a scan gauge on me :(
Looks like the easiest access is through the driver's side tire.
 

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2006 Subaru Outback Wagon 2.5L XT Limited
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I always recommend a transmission additional cooler, as an addition to the stock radiator. I generally warn people against flushing the transmission and just do a drain and fill.
 

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2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
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I always recommend a transmission additional cooler, as an addition to the stock radiator.
A stock Gen 5 Outback already has two CVT fluid coolers, plumbed in series ... a coolant/oil heat exchanger and an air/oil cooler mounted in front of the A/C condenser.. How many more do you want? How many more do you think you need?
 
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Discussion Starter #7
Flushed the fluid today through the cooler. Used the inlet hose on the transmission (picture in original post) by taking off the driver's side wheel. It went pretty smoothly. I shifted gears several times. Unfortunately the old brown fluid stopped flowing after 2 gallons exchanged... so I'm not sure where the other 3-4 quarts were. I got 9 quarts exchanged in total and spilled about 12oz. Transmission downshifts way smoother now imo. Similar smoothness to putting in 110w oil in the differentials for the first 5k miles (note I don't recommend that as subaru says 75w-90 is preferred rear and 75-80 front or something. Also 75w-110 kills about 2-4mpg).

Also grabbed a CVTF oil sample. I'm at 32,575miles. I'll post the sample results when they arrive. Probably 2 weeks. Old fluid was pretty brown, but not shiny (didn't see almost any metal even with a flashlight, didn't see any carbon either which I guess makes sense). Fluid still was tacky and not "splashy" nor mechanically worn.

I'll post a video like someone asked. Don't flame my lamness hahah - I'm not used to making videos. Perhaps it helps someone.

In summary, unless you qualify for the "severe service" I wouldn't do the cvt fluid before 60k miles. But seeing mine be very brown (but not shiny with metal), I also would not wait to 100k miles. Just an opinion.

Oh also I temp gunned the fluid and the pan. When i drove the car 5mins and let it cool for 30 minutes the pan was 122F and the fluid was around 117F. After letting it sit for 2hr and then warm up again the pan was around 105F when the fluid exiting was around 100F. So the pan on the bottom of the transmission is pretty similar.

Also the factory fill let approx 6oz of fluid come out pre-change (car running & shifted through all the gears. Left it running in park and opened fill hole. Small-medium steady stream.
 

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Brucey
'17 3.6
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A stock Gen 5 Outback already has two CVT fluid coolers, plumbed in series ... a coolant/oil heat exchanger and an air/oil cooler mounted in front of the A/C condenser.. How many more do you want? How many more do you think you need?
Sup?

8095730428988288771-account_id=1 (1).jpg
 

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Discussion Starter #9
Woah you hit 276F?! Woah! Impressive. I sincerely did not see that coming. I really didn't think it got that hot. What were you doing to get it that hot?

Also is that 229F your engine oil temperature? You're going to make me buy a scangauge lol. How the heck did it get that hot? Mine only gets that hot on big hills on the freeway.

Also the CVT doesn't have 2 coolers. It has 1 warmer and 1 cooler in series (I think). Having both is designed to rapidly get the CVT fluid hot and then maintain the fluid in a temperature range. The radiator is also the size of 1 of my hands.
 

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2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
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Also the CVT doesn't have 2 coolers. It has 1 warmer and 1 cooler in series (I think).
As posted previously, the Outback has both "a coolant/oil heat exchanger and an air/oil cooler mounted in front of the A/C condenser." Yes, they are plumbed in series. The heat exchanger will heat or cool the CVT fluid, depending on the relative temperatures of the CVTF and the coolant.
 
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Was that before or after you installed your own (third) CVTF cooler? (I was aware that your use pattern is far from typical, but I was trying to keep things simple.) Real-world data like that is the only realistic justification I can think of for adding transmission cooling capacity.

It's worth noting that an unlocked torque converter is by far the biggest source of heat input to the CVT fluid ... e.g. when slogging along offroad, uphill or through deep mud, at low speeds. When the vehicle isn't moving, virtually 100% of the engine power at the flywheel/flexplate is being converted to waste heat in the torque converter. Towing a heavy trailer at low speeds is another good way to heat your CVTF, for the same reasons.
 

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Brucey
'17 3.6
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Was that before or after you installed your own (third) CVTF cooler? (I was aware that your use pattern is far from typical, but I was trying to keep things simple.) Real-world data like that is the only realistic justification I can think of for adding transmission cooling capacity.

It's worth noting that an unlocked torque converter is by far the biggest source of heat input to the CVT fluid ... e.g. when slogging along offroad, uphill or through deep mud, at low speeds. When the vehicle isn't moving, virtually 100% of the engine power at the flywheel/flexplate is being converted to waste heat in the torque converter. Towing a heavy trailer at low speeds is another good way to heat your CVTF, for the same reasons.
I just wanted to show that the stock cooler isn't up to the task in certain situations.

This was after some "light" off road. Stuff that typically wouldn't even make it into a video of mine. Just a long grade at <10 mph. Logging truck road. I couldn't really go faster with as rocky as it was.

It was before the auxiliary cooler though. This trip is what convinced me it was a good idea.
 

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Brucey
'17 3.6
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Woah you hit 276F?! Woah! Impressive. I sincerely did not see that coming. I really didn't think it got that hot. What were you doing to get it that hot?

Also is that 229F your engine oil temperature? You're going to make me buy a scangauge lol. How the heck did it get that hot? Mine only gets that hot on big hills on the freeway.

Also the CVT doesn't have 2 coolers. It has 1 warmer and 1 cooler in series (I think). Having both is designed to rapidly get the CVT fluid hot and then maintain the fluid in a temperature range. The radiator is also the size of 1 of my hands.
The 229F is the water temp.

I'm surprised I only got a transmission overheat light.

The temp gauge still read perfectly level.

Which tells me it's dumbed down a lot and near useless. No wonder they replaced it with a light (and undid it later) on the Gen 4. That's basically all it is anyway.
 

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Discussion Starter #14
That is absolutely insane. That’s so much different than my old stick shift tacoma which most times wouldn’t go above 185F. I guess im going to watch that 3rd heat exchanger install and potentially copy it. I always knew Subaru’s ran hot, just didnt think it was that hot.
 

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Leave it to @Brucey to hold the high score. :ROFLMAO:

I'm pretty sure I've never seen my CVT temp higher than or even close to my coolant or oil temperature.

Mine often looks more like this:

493335


Of course sometimes I start off with temps like this in the winter when the block heater has been plugged in:

493336

493337


Even my sauna doesn't usually get up to Brucey-like temperatures.

493338
 

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2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
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I'm pretty sure I've never seen my CVT temp higher than or even close to my coolant or oil temperature.
FWIW, here are the highest temperatures I've observed in our 2016 Outback 2.5 (TR580 CVT), over 50,000 miles of paved road, unpaved road, and occasional light off-road driving ... at elevations ranging from ~500 feet to ~12,500 feet and at ambient temperatures as high as 108 F:

Engine coolant = ~215 F max (~200 F is typical)
Engine oil = ~238 F max (210 to 225 is typical)
CVT fluid = ~215 F max (180 to 195 is typical)

Under most conditions, CVTF temperature seems to track about 10 to 15 degrees F below engine coolant temperature. Clearly, for our driving patterns additional CVT fluid cooling is not necessary. (There's no substitute for your own data!)
 

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Discussion Starter #17
Anyone know the if subaru sells a gasket for the cvt pan? Next time I want to drop the pan and clean the magnet just because. Didn’t see a part number (I might be blind though).
 

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Anyone know the if subaru sells a gasket for the cvt pan? Next time I want to drop the pan and clean the magnet just because. Didn’t see a part number (I might be blind though).
There is no preformed gasket. It’s a form in place gasket ... Subaru uses threebond 1217g (or equivalent). Permatex makes RTV that works (the ultra black)
 

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Discussion Starter #20 (Edited)
Just got the transmission result back. Said the car showed double the wear mileage of a typical subaru (approx. 60k). I wonder if the cvt doesn't like to be driven certain speeds. Anyways glad I changed it. Like I said, it shifts way smoother now, but also accelerates slower. I'll probably have to follow the severe service schedule even though I don't tow. If you read the fine print almost everyone probably qualifies for severe service. 85mph, short trips (aka grocery store), etc. I stand behind what I said originally where I would change the CVT oil around 60k miles for most people, other than that probably not worth it unless you're doing hill climbs, going over 85mph, or towing regularly.

Never drove the car hard when cold. But have a couple times when warm. Anyways here's the report. See you guys in 5 years on the next flush lol.

Edit: also note how good the viscosity is. I had said the oil showed very little mechanical wear when I drained it. Good to see results like that confirmed. Very solid oil they put in these cars in terms of sheer strength.

Edit2: I'm coming so close to going back to a stick shift car. 15 years of stick and this is my first auto and i'm going through a HARD period of withdrawal right now. It's like impossible to find a wrx hatch or sti hatch that isn't beat to **** though.

494170
 
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