How to Drain/Refill Automatic Transmission

Pan temp or TC temp?
I have a 2012. I ASSume itd be safe doing at 105-115 degrees?
Thanks!

 

That should be fine, I’ve seen the 115-130°F specification in FJ Cruiser documents specifically. They share the same trans with the Tacoma and several other vehicles, so I don’t know if there was a change/update to the temp check range of all A750 transmissions at some point or if it’s different depending on which application this transmission is used in. It could be that the 115-130° range is incorrect or was incorrectly stated.

If some of these trucks do in fact check in the 115-130 range, then you could just check them all at 115°F to be safe, that is the temperature that the 2 given ranges have in common.

If you pull the check plug when the fluid is on the warmer side of the range you will let out more fluid than you would if you pulled the plug when the fluid was on the cooler end of the range. Someone on a 4Runner forum said that the 15°F difference (checked on cool side, then again on warm side of temp check range) equated to about 6oz of ATF on their 4Runner.

I always pull the check plug on the cooler side, but anywhere in the range is close enough.

Think of it like having a transmission dipstick, there is a ‘hot’ range with a length of crosshatching that represents the correct fluid level, anywhere within the crosshatching at the specified temperature range is fine. On most cars with a dipstick you check the fluid level with the car warmed up(fluids up to operating temperature), idling and in park. This is the same thing, there’s just no chance of misreading the dipstick on these transmissions. I actually love the way Toyota has done the ‘temp check’ procedure on their vehicles. I’d rather do it this way than mess with a dipstick, it takes the guesswork out of it. If you have enough fluid in the transmission it’s a one and done deal, pull the plug, let the excess out, replace the plug... you’re done. That’s it.

All I know is that my trucks temp check light is on between 97-115°F.

In park the temperatures are very close to each other. I’ll upload a video of it soon. The light corresponds with the pan temp IIRC, it’s been a year and a half since my last transmission service.
Edit: here’s the video

 

Made myself an OBD2 plug with the wires already jumped out so I don’t have to jam a wire into my truck’s ODB2 port. One day I might solder the wires. I just need to learn to solder, lol

 

Went to dealer today and bought 4L (4.3qt) of ATF WS, followed the procedure and drained liquid all was fine, but then when I messured how much liquid I got out of tranny ... shocker ~5.4L (~5.7qt) and no I didn't drain engine oil.

Is that normal?

Going to dealer tomorrow to get another 2L before I start testing level.

2012 Tacoma V6 4.0L

 

So it all gets a bit more interesting for me.

After looking at all possible places I couldn't explain why there was so much fluid that came out compared to everyone else and I did put 4L back in, so I decided to warm-up truck and see if anything comes out of the overflow plug, and ... ~1L did come out until stream turned into trickle.

That would bring total ATF added to ~3L/qts, which would mean that some mother- overfilled transmission by more than 2L?!?!?!

Will let it sit overnight, warm it up in the morning and see what comes out of tranny and go from there I guess.

 

It should take about 3.2 quarts to drain and fill.

 

That's where it sits right now after drain and re-fill - 3L/3.2 quarts in, 5.3L out... So I am guessing somebody overdid it last time, whenever last time was.

 

Sounds like it. If anything, these are usually under filled from the factory.

What’s the story on the truck before you bought it?

 

Don't know bought it from a dealership (not Toyota), it has 140k miles on it and I talked to Toyota dealer yesterday and there are no records of it having done any transmission work. That said there is a 4 year gap in service records, so they serviced it elsewhere for sure.

 

Re-tested this morning and now I am about 99% sure somebody overfilled it last time by ~2.3 Liters.

Here comes weird part - is there something different about AT Temp Light in 2012?

I initially did wire method, light came up after while and tested level, which seemed to be good - little trickle.

But then plugged in OBD2 reader and checked temperature it was at 97F/36C (AT Temp Light ON), waited until it warmed up to 115F/46C according to OBD2 and procedure here, checked level, ~100ml came out - good.

Here comes the part that I don't understand when OBD2 says it's at 115F/46C, but at the same time AT Temp Light if flashing when I do wire method.

Are there different temperatures used for testing for 2012? Level is within 100-150ml of perfect level now with either method. Just trying to understand what is what.

 

Don't frett over 100ml man. the whole thing takes 4 gallons.....100ml is a drop in the bucket.

 

My 07 checks in the 97-115°F range too.

 

After a couple months of back and forth I finally nutted up and did this. My truck has 155k miles and I got it at 138k with an unknown service history so I figured it was time.

Followed this procedure exactly, minus the wire due to having the Torque app specifically for monitoring temps. I filled it with about 3 2/3 quarts just to be safe bc I am paranoid and got out probably somewhere between 1/2 and 2/3 when checking. Checked at 115 on the app/obd2 reader. The excess fluid came out so quickly I almost shoved the check plug back in, but then it tapered to a nice drizzle quickly.

Here’s a comparison of the stuff I drained to new fluid. Mine was obviously due.

 

This was so much fun for my Taco, I think I'm going to flush my mom's 2009 Honda CRV transmission as well.

 

Hi guys, first off, I have a second generation 2005 Toyota Tacoma Prerunner SR5 2WD, quad cab, long bed. I do have an automatic transmission temperature light in my cluster by the tachometer not sure why yours doesn't but I would definitely look into it. My problem begin at 156000 miles when I threw a rod and blew a hole in my block two weeks after an oil change. This was however after an accident and I'm sure that had something to do with it although my insurance company doesn't agree even though the block was cracked and broken right next to the motor mount, driver side where majority of the impact was but this is not my issue. I did a full motor swap put in a 2011 long block with only 79000 miles so I'm pretty stoked about that. So since I was doing all that I figured I'd drain and change my transmission fluid and filter while I was at it. Unfortunately I had not read this thread beforehand and did not measure the amount of fluid that came out of the pan but it was more than three and a half quarts I can assure you and I was very surprised by the amount. Upon trying to refill it I have now put in 7 quarts and I'm scratching my head like crazy. I followed each and every one of these steps and filled and checked so many times that I've lost count. Is there any way possible that the torque converter could have drained itself while the truck set motorless for almost a month? Has anyone else ever had to put this much fluid into it? Also is it possibly because I disconnected the transmission lines to do the motor swap and more fluid did drain out of those while it sat motorless for over a month. Im beyond confused at this point because I am not a mechanic and this is my first motor swap ever and that was easy compared to trying to figure out how much more fluid I'm going to need to put into my transmission before it's safe to drive. I apologize for the length of this post, just trying to give you as much information as possible to figure out what the problem is.

 

Since you really don’t know how much was in there before or after you drained it, the only thing you can do is add and check. You don’t really know how much came out cause you never measured it. Just fill and check and you will get it. That’s what the procedure is all about.

 

I just ordered a magnetic filter for my tranny.

$26 Magnefine 3/8" Magnetic Inline Transmission/Power Steering Filter

https://www.amazon.com/Magnefine-Ma...ine+filter&dpPl=1&dpID=41AIMNFUURL&ref=plSrch

 

How do you check it? How do you know when it’s time to replace it?

 

Service life is 30,000 miles

 

I thought about something similar. Just attach a super strong neodymium magnet to the outside tranny pan.

When its time to do a pan drain, just remove the magnet, pull the plug and drain as usual, hopefully all the metal residue will drain out with the old hot transmission fluid.