ATF foaming up

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So i did drain and fill on my pilot in singature yesterday, drain 3.5qts and put the same amount back in. Drive the car, got it nice and hot, checked the level as per manual - right on the middle. This morning pulled the dipstick and the level was twice as it should be(?!). I went ahead and started the car, ran through the gears, shut it off and pulled the dipstick - foamy ATF on it ([censored]). Level read between the dots. Foaming was gone in a matter if seconds. Ok, drove the car for a few miles, deives just fine, checked the level again - slightly above min as it was yesterday and no singa of foaming.

My question is - what the heck was that???
 
Originally Posted By: parshisa
So i did drain and fill on my pilot in singature yesterday, drain 3.5qts and put the same amount back in. Drive the car, got it nice and hot, checked the level as per manual - right on the middle. This morning pulled the dipstick and the level was twice as it should be(?!). I went ahead and started the car, ran through the gears, shut it off and pulled the dipstick - foamy ATF on it ([censored]). Level read between the dots. Foaming was gone in a matter if seconds. Ok, drove the car for a few miles, deives just fine, checked the level again - slightly above min as it was yesterday and no singa of foaming.
My question is - what the heck was that???


Probably the ATF coming out was warmer than the one going in and you may have overfilled it.
 
Good one. But these transmissions are to be checked with engine off
 
Unlike most other cars, Honda automatic transmissions are checked with the car OFF

Honda uses a different design than other automatics out there. For one, they don't use planetary gears, but rather, something more like an automated manual, with gears like a manual but engaged by hydraulics.

Only recently has Honda begun using outside transmissions like ZF.
 
Fluid out was slightly warmer than fluid in. And amount if the fluid out and in are very close to te book number. So it wasn’t overfilled for sure
 
I’ve driven it for a good 15-20miles and checked again - level is spot on. And it was yesterday wheneve i changed it and drove for a couplenpf miles. Just weird and makes no sense. Any possible harm to the trans with that foaming event?
 
If its leaking down because the sump is empty when you drain it then probably not, the air got pushed out in a few seconds along with some fluid so it was not dry. Air goes to the top, the pickup was still drawing liquid.
 
It just doesn't make sense why was there so much fluid in the sump this morning. Like I said, I added slightly less or the same amount as drained and it matched the book number. Plus the car has been driven and level checked OK. could the fluid from TC drain down to the sump through the night and overfill it?
 
The TC drains back overnight. Only perform fluid level checks with the ATF at proper temp.
 
I was always checking it warm and after the car has been driven. I was surprised to see that SO much has drained overnight and even more so when it got airated
 
Nope. Level is spot on and no foaming at all. I've checked the level several times both with the ATF up to the temp as well as after sitting overnight. i'm really confused as to what happened where and why
 
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