Overfilled Transmission Fluid?

[stratwielder]

I think I overfilled my transmission fluid. During my spring break I decided to change the transmission fluid because recently it's been feeling a bit hallow when I shift. Since I changed it, it feels buttery smooth. However, I've read that it only requires 1.6 quarts per fluid change. I put about ~2 quarts in and some of it was coming out when I was putting the fill bolt back in.

Could this possibly damage my car? Also, is there any way to check how full it is, like the oil dip stick?Thanks in advance for your help.

[Cheep3]

I refilled mine exactly the same about 6 mos. (& 10k miles) ago. Same 2 qrts. and some ran out before I put the plug back in. No problems. In fact I didn't really notice it at first, but now it shifts noticibly smoother (especially first to second gear) after switching to Redline MTL. If you put in less than 2 quarts I don't think there is any way you can do any harm.

[stratwielder]

Ahh cool. Thanks for the input man. I got all worried over nothing.

[kenscivic]

The way you know your tranny is full is when it starts coming out through where you are filling it up. It is literally the closet thing to impossible second to floating in your living room and getting holes in your hands.

[2k3hatchie]

Phew, I had gone by the amsoil product application guide when I ordered my 2 qts Redline MTL.

[HondaFreak]

Sorry to say, but overfilling IS bad. Yes it can cause damage. I remember asking a friend about this. It has something to do with too much fluid to move. Don't forget there is high rpm rotations going on in there. Depending on the thickness it gets worse the thicker it is. If you leave it "overfilled" for a long period, YES, you'll do damage. Syncros in Honda transmissions are easily messed up, that's 95% of the shifting mechanism. Make sure you follow your manual to the "T". That oil is only lubrication, not cooling.

Christian

[bmyers4321]

Agreed with Hondafreak over filling the trans is bad. To much will cause excessive pressure and blow seals. Also it will foam and bubble causing that to be lubricating instead of the actual fluid. But, as far as what you have done you should be ok. Working at a dealer previously and still working on vehicles elsewhere other mechanics and i always fill MT till they start to overflow from the fill hole. I like to let it run out till it stops then cap it off, but to each there own.

[Rekognize]

Sorry to say, but overfilling IS bad. Yes it can cause damage. I remember asking a friend about this. It has something to do with too much fluid to move. Don't forget there is high rpm rotations going on in there. Depending on the thickness it gets worse the thicker it is. If you leave it "overfilled" for a long period, YES, you'll do damage. Syncros in Honda transmissions are easily messed up, that's 95% of the shifting mechanism. Make sure you follow your manual to the "T". That oil is only lubrication, not cooling.

Christian

Agreed with Hondafreak over filling the trans is bad. To much will cause excessive pressure and blow seals. Also it will foam and bubble causing that to be lubricating instead of the actual fluid. But, as far as what you have done you should be ok. Working at a dealer previously and still working on vehicles elsewhere other mechanics and i always fill MT till they start to overflow from the fill hole. I like to let it run out till it stops then cap it off, but to each there own.

Thanks for the tip, changed my trans fluid today and I overfilled it by ~500ml. After reading your comments, I went back to the garage and drained it to spec (1.5l)

[gtolio]

Impossible!

I'd like to see some actual Honda manufacturers recommendations on this. When I changed it on mine (whilst following the Honda Service Manual), I distinctly remember filling it until it came out of the hole. 500ml is quite a bit (half a nalgene). It would surprise me a lot if the hole wasn't designed that way.

Now I have to check the service manual dammit.

EDIT: From the horses mouth. Take special note of the fluid level indicated in figure 2c showing that if the car is level, it would be impossible to overfill. It does however indicate that the amount required to reach this level should be 1.5l. I suspect your car wasn't level. If I were you, I'd be worried that it's too low now. I'd take overfilling over underfilling any day. Guaranteed, underfilling is the faster way to screw your tranny up of the two.

[Rekognize]

My driveway isn't level and I used a clear hose with the exact same diameter as the fill hole and filled it using a funnel from above. I did overfill it—I emptied 2 quarts in there

[gtolio]

My driveway isn't level and I used a clear hose with the exact same diameter as the fill hole and filled it using a funnel from above. I did overfill it—I emptied 2 quarts in there

Yeah, just to be clear, it IS possible to overfill it if the car isn't level. Think about if you poked a hole in a coffee cup, then filled it with liquid. If you tilted it one way or the other, it would affect how much liquid you could put in it. Same concept here.

[captaingamez]

That oil is only lubrication, not cooling.

Christian

This is an old thread but I hate wrong information, assumptions and BS.

All oil is there for two purposes ALL OIL IN NEARLY EVERY PIECE OF MACHINERY ON THE PLANET.

Its there for LUBRICATION and COOLING.