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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #1
After I drive my 2000 H4 2.5L OBW long enough for it to warm up, when I check the trans fluid the dip stick "pops" when I take it out without the engine running, the ATF flows out of the dip stick tube. It literally burbles out like the fluid is way overfilled. It seems a bit clunky when shifting up or down. Sometimes at stop lights I smell something hot or burning. I assume it is the ATF flowing out and hitting the manifold. Otherwise it runs fine and shifts well enough to get around. Also, the fluid level looks fine (a 1/4" high due to my earlier work - below) when the engine is running.

I noticed it was high the last time I checked it, so I took a siphon and sucked out a couple of quarts. After checking it with engine running it seemed a bit low, so I added a quart and it seemed spot on. The fluid I took out looked pretty brown so I order an OEM Subaru filter and was planning on changing it, using the method I read about here: http://www.subaruoutback.org/forums...anging-automatic-transmission-fluid-easy.html

I don't think this is normal and hope someone here can give me a clue as to what the problem might be.
 

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2001 VDC/SC One of a Kind
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There are vent tubes running from the top of the transmission that may be clogged. The pressure is building within the case and when you pull the stick, the pressure is released.

When pressure builds up, flow suffers, so it is possible that the clutches may have begun to slip, you just haven't noticed it much because of the adaptive shift programming in the TCM.

Flush the system good. Pull off the vent tubes and clean them out. If the tubes end up being free from debri, you have an issue with venting inside the case.
 

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If the vent tube cleaning doesn't change the over flow issue. Another possibility good friend had this very same issue with a Ford for years and years took it to several different dealers and got the same old story. 5yrs of this finally some old grizzled mechanic at the local dealer listened to his description of what was happening took a 30 second look at the truck and told the lacky shop crew to check the cooling lines and cooler for any blockages. Bingo blockage in the cooler caused by a rock strike that pinched the feed line. New cooler and the old truck was perfectly fine he had it till just 2yrs ago 200,000 miles the last 100K was trouble free of the AT fluid over flow issue.

Good luck

For sure flush it good and clean up the vents see how that goes.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #4
OK, can you guys describe where the vent tubes are? Will I be able to see or find them when I am under there to change the ATF and filter? Any suggestions on how to clean them - coat hanger, compressed air, etc.?

I had a radiator flush and fill when I had the timing belt, water pump, idlers, etc, done. Could something during that process have caused these symptoms?
 

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2009 Tribeca Now - 2004 Outback EJ259 - Sold
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They are located on the top of the trans under the firewall/bulkhead.
Behind where the air intake bracket support bolts to the transmission.
In this photo the black line on the RH (passenger) side is the transmission vent.
The line on the LH (drivers) side is the front differential vent.
 

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There is also another slightly different vent tube design, but the vent location is the same.
The small upside down U shaped tube is the trans vent.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #7
So they are the two hoses in your pic running from the top of the trans over the electrical connectors just where the trans mates with the diff, forward of the filter but NOT the metal and rubber tubes right beside the filter?

Bear with me. I've never done any tranny work. Are they accessible? If so, how would you recommend unclogging them?

Could this also be related to blocked cooling lines (mentioned by Subiesailor above) that may have occurred during my recent timing belt/water pump replacement and cooling system flush and fill?
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #8
The small upside down U shaped tube is the trans vent.
It's much easier to see in that pic. Same questions as above though.
 

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Yes the 2 lines on the top of the trans.

Depending on the size of your hand and how flexible you are they can be accessed from the top.
They are in a tough spot to reach, from the bottom may not be easier since the exhaust is usually blocking any ability to reach up that high.
To (check) unclog them simply disconnect from the vehicle, remove and blow out with compressed air.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #10
I'll give it a shot and let you know how it goes.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #11
After rolling up my sleeves (literally) and cramming my long skinny arms (I knew not working out would pay off some day), up into the greasy bits, I discovered I have the trans type pictured in post #6 above. I was able to get the little U-shaped tube off and it was completely clear. I blew air through it with my mouth (yuk). It was a SOB to get back on since I was working under the car on jack stands. I was not able to find the other end of the vent hose located next to the U-shaped hose, so I did not remove the end next to the U-shaped hose. I gave it a good wiggle and it seemed to become less stiff. Not sure if that helped or if I need to remove and check that one.

My other question is related to post #3 above: Could any of the overflow problem be caused by the work done during the timing belt and cooling system flush and fill? I'm waiting for my guy to call me back. He's always been square with me and I trust he'll fix anything that was screwed up during that process. I just want an idea of what I should ask him when he calls. If anything.

If it is not the vent or a cooling system problem then what are we looking at? Major expensive problem? Something I can let slide? The car has 164K miles. The AT check light has not come on. She still shifts fine - maybe do to the TCM compensating. The engine is NOT running hot. The burning smell was from my PS Rack's slight leak. I have CEL for the P0420 code, but plan on using Free SSM when I get a chance, and will bug folks about those readings another day.

I did try using the FreeSSM to check the transmission and I got a message that said: "Communication Error: - No or invalid answer from TCU -" It connected to the ECU just fine.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #12
I just returned from driving about 90 minutes. I left the engine running, ran through the gears, and the ATF did not bloop out of the dipstick tube when I checked it. There was a slight "pop" noise, but it was not as pressurized as the earlier pop when the fluid oozed out. I turned it off and waited a few minutes and the ATF still did not bloop out when the stick was pulled - no pop either. I waited another 10 minutes with the engine off and still no blooping out of ATF or popping. I'll test it a few more times over the next couple of days. If messing with the vent tubes seemed to fix it (fingers crossed), I'll change the ATF and filter.
 

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Sounds like it was just overfilled.
Pick up the ATF-HP (4qt) and genuine A/T filter from Subaru if you do change it.
Going to need a new crush washer as well for the drain plug.

Here is the page from the manual regarding A/T oil level.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #14
Step 7 above states: Bleed air control valve. <Ref. to 4AT-63, Air Bleeding of Control Valve>

I searched the forums and could not get an answer about whether this step is needed. Can someone let me know if I need to bleed the air valve and if so, where it is and how to do it?
 

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Here ya go.
Going to need a dealer Select Monitor for this procedure.
I would say no, you don't need to do this.
But if you can find someone willing to give it a try, go for it.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #16
Yeh, I think I'll skip that. Although, I have FreeSSM, as you recommended in another thread, but it cannot connect to the TCU - see post #11 above. Could this be used to do that procedure? If so, how can I get it to communicate with the TCU?

BTW, I drove my round trip to Baltimore (about 90 mins) and when I checked the ATF with the engine off, the fluid flew out of the dip stick tube. It gurgled like there was air in the system. It was not hot enough to burn my hand. If I check it when the engine is running it is fine. Any ideas other than the U-shaped vent hose, which checked out OK? Perhaps the bleed is needed.

I'm going to change the ATF and filter to see if that helps. Can't hurt. Though I may be out the $31 I spent on Dextron III.
 

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You need to check it with the engine running.

How much fluid is coming out when it "gurgles"?
Chances are its just an air pocket developing inside the dipstick tube & it tries to escape when you pull the dipstick pushing up the fluid in front of it with it.
Doesn't seem too unusual since the dipstick tube extends down into lower portion of the case & the fluid rises when you shut the vehicle off.
Could be developing an air pocket for some reason.
Can't say I have ever had a reason to pull the A/T stick after I shut the vehicle off.

If FreeSSM isn't connecting to the TCM chances are it wont, the program has a few nuances.
 

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In answer to the several questions:

The valve bleeding is only necessary at build or rebuild.
No the radiator flush could not cause blockage in the Trans cooler portion.

Next step would be to have the Trans cooler portion of the radiator force flushed and check the lines/hoses. Or just have a full system flush with a machine that allows for large quantity fluid flow. Out with the old, in with the new. It may be a good idea just to bypass the radiator all together and install a separate Trans cooler.
 

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Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
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Discussion Starter #19
Here's where I stand: I've drained about 6 quarts, installed the new filter and replaced the crush ring on the drain plug and snugged that back on. Added 6 quarts of Dex/Merc III. BIG QUESTION: Is the fluid supposed to "Burp" as I am pouring it down the dip stick tube?

Drove around for about 10 minutes, turned it off and pulled the dip stick - slight pop but no fluid. I think I am just going to stop pulling the dip stick while the fluid is hot and the engine isn't running. Might be like opening the radiator cap when it is hot.

Started it back up, ran through the gears, checked it while running and it shows the fluid barely up to the COLD LOW mark. I am reluctant to pour more in because I had too much before. Can I or should I drive it like this for a while to see where it settles? Or should I pour more ATF in because the stick is reading true and ain't gonna change? BTW, I am reading the actual level and not the fluid that clings to the side of the stick.
 

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it helps to lay the stick aside while you run through each gear for 5-10 seconds. maybe even wait a little after that, then take a reading. Cold is tricky, I mean, starting at minus 20 is different a 102 degree temp at start. But warm means operating temp with the fluid running through the radiator and may be a more 'accurate'/repeatable reading.

also, the marks are not like an engine oil dipstick, there may be only a pint of fluid difference from cold to warm - add small amounts, recheck frequently after waiting for fluid to drain from the tube.
 
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