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transmission problems after fluid change


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Recently changed my tranmission fluid but I put too much in. I drove for 100 or so miles then I saw it was too high.I drained and filled it with the same fluid now it has torque bind. How badly did I screw up my transmission?

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i already replied to your question, what happened to that thead/post?

 

highly doubtful the overfill caused this.

 

more than likely there were issues present before the fluid change - you changed the fluid hoping that would help - and it's still bad.

maybe the new fluid induced higher (back to normal) pressures that exaccerbated an already existing issue - but if that's the case it was just coming around the corner anyway.

 

is it in limp home mode (like only in one gear and wont' shift 1st - 2nd - 3rd?  Or is it only having torque bind?

 

important details:

 

1.  how much was it overfilled?

2.  did it blow out the dipstick or vent tubes on top?

3.  vehicle

4.  year

5.  mileage

6.  why did you change the fluid?

7.  is the AT light blinking 16 times at start up?
8.  is the check engine light on.

9.  how long have you owned the car?

10.  last fluid change?

11.  what did the old fluid look and smell like that came out of it - clean, black, or in between?

12.  trans pan isn't dented?

13.  does the torque bind go away if you install the FWD fuse in the FWD fuse holder on the passengers side strut tower

Edited by grossgary
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Sorry I was posting on my phone and it posted twice.

It was overfilled by a quart.no fluid blew out it just had bubbles in the fluid.it's a 93 impreza awd auto with 300k now.I changed the fluid because I just got the car and thought ut would help.yes it flashes the code for the duty c But it has been since I got it.the first fluid I drained was very black and smelt bad.The fluid I reused was in between.the whole time it was overfilled it had no torque bind but after I drained and refilled it its been very bad. No the fwd doesnt help.I was going to try refilling with new fluid

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or maybe the product is old? I could find ADvance Auto parts labeled bottles of ATF for several formulations, including Dex/Merc (DEXRON II and III) but AutoCraft seemed to just be on some AAP batteries???

 

anyway, dannybito just needs to confirm it's Dexron 'compatible' was all I was thinking.

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yeah, drain and fill only gets about half the total fluid.

 

drain/fill/drive repeat 2-3, times gets 80-90% new fluid.

 

you 'could' try a different brand of fluid and/or a CRC or Lucas additive.

 

definitely go thru GG's list especially number 13.

 

I'd wait if possible til GG replies to this thread though. he has a lot of experience. I only read about the stuff he and other gurus do.

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Im thinking when I reused that fluid it probably wasnt all clean and its messing things up.hopefully I can get it all out.thank you texan. Ill wait for GGs response.also sorry I actually used super tech fluid

Edited by dannybito
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When adding fluid, it is best to put the car in gear to take it on. Also, it is best to cycle through the gears between each drain and fill to clean out all the valving. Try this if you haven't. hold the trans in each gear while idling for about 15 second each.

 

This is how we do at an oil change shop when servicing customer vehicles.

 

Later generation fluids *should* be backward compatible, at least a synthetic trans fluid that works with type 6, 5 and 5, also with type 2 and 3 such as regular ATF (dextron/mercon)

 

Good luck

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Im thinking when I reused that fluid it probably wasnt all clean and its messing things up.hopefully I can get it all out.thank you texan. Ill wait for GGs response.also sorry I actually used super tech fluid

For what it is worth, I have used Walmart Super tech ATF with good results, over many years in my Subies. So, I don't think the Super Tech is causing you problems.

 

I think it is a bad idea to reuse fluid. Just too easy to contaminate with dirt, when draining.

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Just to re-emphasize what was said earlier--each drain-and-fill only removes about 50% of the "old" fluid in your tranny.  You have to do it at least 3 times (driving or idling each time so the fluid circulates and mixes) in order to get reasonably fresh fluid in there.

 

Seems a bit wasteful but if it solves your problem it's definitely the cheapest fix.

 

Super-Tech is fine.  I've used it for years in various Nissan and Toyota AT cars my wife has had--no problems.

 

Good luck and do keep us up on your progress!

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Pan isn't dented - you didn't mess with the pan at all?

 

Make sure the fluid meets the Subaru required specification.  Other than that brand is insignificant.

 

You have a failing Duty C solenoid
 

*** If you're really lucky maybe changing the fluid a few times may free up the sticking Duty C solenoid.

You need to change the fluid at least 3 times to get a reasonable amount of the total fluid changed.  AT fluid sits up in the torque converter and valve body and a simple drain only gets about 1/3 of the fluid out.  Or set up a bucket system where one transmission cooler hose sucks up new fluid while the other hose dumps old fluid into another bucket.  when you start seeing clean fluid come out, stop.

 

In generally though - a failing Duty C usually gets worse, not better.

 

*** Remove the rear half of the driveshaft and drive the car in FWD. You can drive it indefinitely like this.

For extra protection leave the FWD fuse in place just in case the solenoid decides to start working - so the car is in FWD should it start working again.

 

In the end, if fluid changes don't work - just run it in FWD indefinitely.

Or replace the Duty C solenoid.

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Ok did 3 drain and fills.driving a bit each time.going through all gears when draining and on the last fill I put a bottle of lucas in.

 

Now the torque bind is much better. It still happens when I turn right.I have it in fwd and it doesnt help. Im thinking of driving for a week or so then doing another drain and fill. I will change the differential fluids this weekend.80w90 in both the front and rear?

 

If it still binds in fwd does that mean something else is wrong besides the duty c? I only ask because im considering putting a transmission in but I am unsure since the engine had 300k.

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I believe they are all the same.

"I believe" and "i am certain" mean 2 different things. If you do have odd size or unevenly worn tires, mount the 2 best matching diagonal from eachother.

Edited by MilesFox
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what he said - the tires have to match on a 4WD vehicle.

 

the FWD fuse will not work with if the Duty C solenoid is failing.

 

if the torque bind doesn't go away with the FWD fuse - that simply means the Duty C solenoid is failing.

 

you don't need a new transmission - you only need a new Duty C solenoid.  they're easily replaced without dropping the transmission, no point in doing all that extra labor when it could be easily repaired.

 

get a use extension housing with Duty C or just a used Duty C if you're interested in saving a few bucks.  for the time crawling around on the back though i'd prefer a new Duty C, but just depends how much time you have, etc.

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If it's a Duty C, it would be better to shortcut all the fluid changes and fix it - which involves a fluid drain anyway.

 

As for some slight dirt getting into the trans, the pickup screen doesn't begin to filter it out, which also includes any metal or clutch fibers that shear off. It's all dependent on the screen size, as a fibrous filter element isn't used until after it's pumped to the spin on filter - which Subaru specs as a high bypass, anyway. 

 

What little dust or dirt the catch container and funnel might have in it from being diligently cleaned won't be as much an issue as what might still be trapped in the torque converter. I examined mine after removal from a major failure and it's ugly seeing flakes of bearing and clutch material shining back at you down the insides. I used the newer one provided with the trans as it was clear and clean. 

 

Goes to any funnel we use to pour in fluids - if road dust can get on them, we flush it right down the fill opening. I finally woke up and keep it in a plastic bag to keep things clean both ways.

 

Time to mention that using RTV sealant on the pan isn't recommended. A gasket is the preferred item, as RTV is known to dissolve in the presence of ATF, which is 60% detergent additive. I spent an hour and a half cleaning it off my pan rails with a plastic scraper and plenty of paper shop towels to keep the tiny flakes out of the trans. Any one of them could get trapped inside the valve body and cause things to stick. 

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