I just drained my Transmission

Hi everyone, Well I just got my 2011 Tundra TRD 4.6. I bought it with 284,000 mls on it. Rather have a Toyota with 284,000 mls than any other pick up with half the mileage. So yesterday I made my first bone head move and went to change my oil. What did I do? I drained the darn transmission pan instead of the oil pan. I realized what I did but it was to late. There I was looking at roughly 3.5 qts of trans fluid sitting in a contaminated oil catch. After talking to myself and calling myself every name in the book for an hour. I ran down to Orileys auto parts and proceeded to make my second mistake and purchased a gallon of what they said is an equivalent to WS synthetic oil. I measured what I drained and put back the same amount of new fluid that I took out. (Fun experience ) When I looked for videos on how to know if I had proper fluid level in the transmission. I found "Car Care Nut" a master Toyota technician who does DYI videos for Toyota owners. I followed the official Toyota method of using the trans temperature mode by jumping pins 4 and 13 in the OBD2 connector and using the dash lights. I ran into problems. First I couldn't find a way to get the truck completely level no matter what I did. Second the dash lights blinked but no matter how many times I tried I couldn't get into transmission temperature check mode. I decided to just take it to Toyota and have them do it right so I set up an appointment and jumped in the truck. Backed out of the driveway and put it in drive and the transmission started slipping. I got it back in the driveway and shut it down. Called a tow truck and had it brought the shop. Now I'm sitting here with my stomach turning. Hoping I didn't screw up a 284,000 mile transmission with new fluid. As you know putting new fluid in an old tranny can cause serious issues. Especially when you put Dexron V1 in a WS transmission. Essentially I put dollar general oil in there is what I found out . I have always wanted a Tundra since I first looked at the 2007. I finally got one in beautiful shape and I messed up. This truck is like brand new the undercarriage is ridiculously clean and rust free the body and interior are the same way and the engine runs smoother than my wifes highlander with 144,00 mls. I'm committed to this truck and I'll do whatever it takes to fix it. I sure do hate myself right now. Sorry for the long post.

 

New transmission fluid won't hurt an old transmission. That's a bit of a perversion of the concept that a transmission flush on an old transmission will break loose old deposits and cause problems. Regular drain and fills on the transmission should be totally fine.

That said, quality of fluid does matter, and that I can't speak toward as I don't know enough about the additives and properties in them. Still, I'd doubt you messed anything up that you can't get working better with a few drain and fill cycles with proper fluid.

 

Transmission fluid is just hydraulic oil. I wouldn't think a few miles (if that many) of driving with cheap fluid would cause damage.

It seems like there's 5 people a month on here who have drained the transmission accidentally while changing the oil, so you are definitely not the first.

I'll bet Toyota will get you fixed up no problem.

 

It will be fine. Stop driving as soon as slip is detected was what saved it. A few consecutive drain and fills with proper fluid will cure it.

 

Welcome.

Do yourself a favor and read through the manuals.

https://www.toyota.com/owners/warranty-owners-manuals/