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Guest Message by DevFuse

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Transmission fluid in Antifreeze

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6 replies to this topic

#1 silviajeff



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Posted 09 March 2013 - 06:41 PM



I have a 2005 Subaru Outback LL Bean with a 3.0 6cyl.  I am getting transmission in the anitfreeze.  I thought it was a bad radiator, but I have installed a new radiator and I am still experiencing the issue.  How can transmisson fluid be leaking out of the transmission and into the antifreeze?





#2 CNY_Dave


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Posted 09 March 2013 - 09:41 PM

I would say it almost can't, and if it were you'd be getting antifreeze in the transmission, which I have to imagine would show on the dipstick.


The pressure in the radiator is higher than that of the trans lines, and the trans line pressure would go to go to zero after shutdown, while the radiator was pressurized.


So you saw red oil in the coolant?

#3 luko


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Posted 09 March 2013 - 11:01 PM

Did you flush out both the tranny and coolant systems? and put a new tranny filter in? if not that should be done, because there still could be a little of either left in the other being that is the only place those two meet

Edited by luko, 09 March 2013 - 11:02 PM.

#4 silviajeff



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Posted 10 March 2013 - 08:35 AM

Yes,  I flushed out the complete cooling system.  We removed the thermostat and completely flushed system while running the car.  We also noticed that some coolant was in the transmission fluid, so we drained what was left.  We replaced the transmission filter and the refilled with new transmission fluid.  We reconnected everything and started the car and let it run with the radiator cap off.  Slowly we started to see the coolant start to turn a thick brownish color.  When checking the transmission dip stick the fluid was gone.  We checked the oil dip stick and it was fine with no signs of coolant.

#5 Hakim Craddock

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Posted 10 March 2013 - 10:53 AM

are you sure its trans fluid and not just red antifreeze? i did some work on a lexus yesterday and it had red antifreeze..whats in the reservoir?

#6 CNY_Dave


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Posted 10 March 2013 - 11:51 AM

Bypass the trans cooler with a piece of hose and see what happens.

#7 ivans imports

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Posted 10 March 2013 - 11:56 AM

in the iner fender well infront of the tire under the plastic wheel well is a inline fillter remotly mouted mabee is some traped in there. Had to have been a rad problem no other place that the coolant meets the atf. But if its oil in the coolant thiss have had many problems with the 3.0 as it has  a layerd pan that has biult in oil coolers and many coolant pasage ways thru oil. Have two of theese 3.0s with milky oil is a problem in the lower pan area

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