Automatic Transmission Fluids (ATF) full 12qt flush & set level, 100 series.
- Thread starter 2001LC
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- #42
That is drain and check washer (gasket).
Fill is a larger rubber O-ring. Which the old is fine to reuse 99% of the time. You can use hardware store )-ring match to size, if you like. Some use the transfer case aluminum washer in place of o-ring.
Fill is a larger rubber O-ring. Which the old is fine to reuse 99% of the time. You can use hardware store )-ring match to size, if you like. Some use the transfer case aluminum washer in place of o-ring.
thank you so much! I was planning to do a pan drain & fill. Is there anything wrong with just doing that (once now, then once every time i change the engine oil, up to 5 times) versus the 12 qt flush all at once? i'm a little hesitant to do the 12 qt flush only bc it seems intimidating for some reason.
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- #44
Drain & fill (D&F) is what Toyota recommends.
But there're issues with doing just a D&F:
But there're issues with doing just a D&F:
- What type of ATF, has been added into AT, in past D&F. Mixing fluid types or brands, is a very bad Idea. Which INDY shops and DIYers, all to often do. 04-up, call for Toyota WS ATF. Many will add whatever ATF, is on the shelve.
- Any insoluble in the AT fluid, are only slightly diluted. Rather than flushed out.
I just did this job last night using @2001LC 's excellent writeup at the top of this thread. I had been procrastinating, and literally as I sat down to research it, this thread popped up. A sign.
The flush described in this thread is easier than I thought. Took me about an hour working slowly and carefully. I have a 99 with a dipstick, so no guesswork about the fill level - 2004+ will require the extra effort to verify fill without the benefit of a dipstick. The hardest part for me was ensuring I disconnected the correct hose. I confused the multiple cooling hoses until I figured out how the cooling loop works:
I started by draining 3.3qt from the pan, replacing the pan drain plug and washer, and then adding 4qt of fresh ATF through the dipstick fill tube (which leads directly to the pan). The system was now slightly over-full. I then ran the engine to drain 2qt, resulting in the system being slightly underfilled. I added 2qt and then purged out 2qt repeatedly until I had a grand total of 12qt out in a graduated bucket and 12qt in through the fill tube. The pan was thus never more than 1qt over- or under-filled while the engine was running. My dipstick levels before and after the procedure were the same.
In my experience, the cooling line purge was at the same flow rate as filling though the dipstick fill tube, so if I were doing it again, I would just purge and fill continuously.
The flush described in this thread is easier than I thought. Took me about an hour working slowly and carefully. I have a 99 with a dipstick, so no guesswork about the fill level - 2004+ will require the extra effort to verify fill without the benefit of a dipstick. The hardest part for me was ensuring I disconnected the correct hose. I confused the multiple cooling hoses until I figured out how the cooling loop works:
1. ATF exits the transmission
- Hot ATF leaves the transmission case through the outlet hard line on the passenger side of the transmission. This is pressurized flow driven by the transmission pump (not gravity).
2. Primary heat exchange: in-radiator cooler
- The ATF line routes forward to the radiator’s integrated transmission oil cooler, located in the lower radiator tank. ATF flows through a sealed tube-in-tank heat exchanger, exchanging heat with engine coolant.
3. Secondary cooling: auxiliary air-to-oil cooler
- After exiting the radiator, ATF flows to a separate external air-to-oil cooler mounted forward of the radiator, on the radiator's (US) driver side. This cooler provides additional heat rejection under towing, high ambient temps, and low-speed off-road operation.
4. Return line back to the transmission
- Cooled ATF exits the auxiliary cooler, runs across the forward face of the radiator, and enters the engine bay just to the (US) passenger side of the radiator, about halfway up the radiator's height. ATF re-enters the transmission case via the return port, feeding lubrication circuits and the valve body.
I started by draining 3.3qt from the pan, replacing the pan drain plug and washer, and then adding 4qt of fresh ATF through the dipstick fill tube (which leads directly to the pan). The system was now slightly over-full. I then ran the engine to drain 2qt, resulting in the system being slightly underfilled. I added 2qt and then purged out 2qt repeatedly until I had a grand total of 12qt out in a graduated bucket and 12qt in through the fill tube. The pan was thus never more than 1qt over- or under-filled while the engine was running. My dipstick levels before and after the procedure were the same.
In my experience, the cooling line purge was at the same flow rate as filling though the dipstick fill tube, so if I were doing it again, I would just purge and fill continuously.
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amazing. would you mind taking a photo of the correct hose to take off? I know there are a couple in the aforementioned write-up, but the more the merrier (espescially if they are zoomed out).
also, my reading comprehension might be shot, but are you using a total of 12 qts of new fluid or 12 + 3.3 qts = 15.3 qts?
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- #47
Consider reading the OP of thread. Better yet read the whole thread.
i have read everything! i just think another picture with the original hose attached would help me feel more confident in doing this job. also you call it a 12 qt flush, but i still am unsure if that includes the 3-4 quarts in the pan.
basically, if i have any doubt or unanswered questions, i won't do a job. but i know i desperately need to change my atf fluid so that's why i'm asking questions that some may feel have already been answered. in my mind they havent.
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- Thread starter
- #49
Look close at picture in OP (#1 post). Copy picture to your PC and zoom in if needed. Picture, very clearly shows, a clear hose attached on nipple (aluminum pipe from AT oil cooler rad) on right side of engine radiator (PS side in LHD). The clear hose, then runs to catch can. The black rubber return hose that came off that nipple, is just sitting to the side.
Also in post #5, it you'll see picture with red and blue arrows. Red is upper nipple with clear hose attached, which is return line you want.
The system holds 12 qts. So count every drop you remove from anywhere. Starting with what is drain out the pan. Then refill fill the pan, before starting the engine. keep level in pan up the whole time. Do not, at anytime run pan dry, while running engine. Running engine, runs AT pump. So stop engine as needed, to stop pumping ATF out of AT. Keep in mind. It will pump out faster than you can poor fresh ATF in.
It's easier than you think. Do a dry run. Make it make, sense to you.
Notes:
- In the 2004 up. Most fill through fill port on side of AT adapter case. To get to fill port plug. Our arm get near exhaust, which will burn arm. So I do 2004 -up, after exhaust cools. I over fill AT by 1/2 qt. so I don't need to get near exhaust/fill plug. During the check level procedure. This is where counting ever drop out and even drop in, pay off.
- I first twist loose hose, breaking bond from pipe nipple. Then push black rubber return hose, off aluminum pipe nipple. I never pull off hoses. I always push off from end of hose. Pulling on a hose, will stretch and tighten on nipple.
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12qt total. What’s important is that you put in exactly the same grand total as you take out (assuming you’re starting with the system properly filled to 12qt). That’s why a graduated container helps.
When you turn the engine off, the ATF you are purging remains a little pressurized and continues to flow, plus your drain hose will hold a little extra. On the final purge I stopped the engine at 11.5qt and got the last .5qt just dripping out over a half minute.
I did a similar flush on my 62 years ago by disconnecting a lower hose and I recall it pissing ATF all over me and the floor. I think what works well in @2001LC ’s write up is that you’re disconnecting the highest possible point in the system, so there is almost no leakage due to gravity.
I am still constantly amazed that anyone believes they can completely change the transmission oil by draining the pan repeatedly. I'm glad none of them work at my local pool.
The reason Toyota recommends draining the pan as opposed to replacing the fluid is that the debris that accumulates in the system falls into the pan, and you can get most of it out by draining the pan. Toyota has never said, or implied, that draining the pan is equivalent to replacing the sytem fluid volume.
The reason Toyota recommends draining the pan as opposed to replacing the fluid is that the debris that accumulates in the system falls into the pan, and you can get most of it out by draining the pan. Toyota has never said, or implied, that draining the pan is equivalent to replacing the sytem fluid volume.
Dilution-draining can get you 95% changed if you're willing to drain the pan 9-10 times and pay for ~8 gallons of ATF. A flush-drain is cheaper, faster, environmentally smarter, and avoids mixing old and new ATF.
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- #53
A good idea is too check level, pre drain of pan & flush. Then you know if working with; over, lower or just right level to start. Which is easy in 98-03. But PITA in 04-up, which would require bring AT fluid up to temp. Then exhaust gets hot and must cool to get at fill plug.
Doing as many as I have. I've gotten very good at accounting for every drop out and in. So if I find, during level check at proper AT #1 fluid temp. I'm low or high. I know, level was not correct.
In the 04-up. I find those ~ 1/3 qt low, from factory. If never properly topped.
So when I add that extra 1/2 qt. plus, at end of flush. I'll get just about 1/8 qt. of a steady flow from check plug straw at 97F, until just drips out. If no flow, more than what straw holds, then just drips. I'll take temp up to 100f, 105f, 110f even 115F or higher. To see at what AT #1 temp it does flow. I'll then add 1/4 plus what I think low. Through return hose, with my larger syringe.
if over, in the 98-03. I hook my hose to catch can back up. Start and stop engine in 1 second. One can also; either disconnect ATF cooler hose from bottom of engine radiator, to drain off a tad. But that usually involves remove skid plate, which I don't for AT flushes.
BTW: A really good transmission shop. Suggest over filling a tad. We're are better over than under. To this end, I set level at very lowest temp range recommended or few f degrees, lower than minimum range.
Doing as many as I have. I've gotten very good at accounting for every drop out and in. So if I find, during level check at proper AT #1 fluid temp. I'm low or high. I know, level was not correct.
In the 04-up. I find those ~ 1/3 qt low, from factory. If never properly topped.
So when I add that extra 1/2 qt. plus, at end of flush. I'll get just about 1/8 qt. of a steady flow from check plug straw at 97F, until just drips out. If no flow, more than what straw holds, then just drips. I'll take temp up to 100f, 105f, 110f even 115F or higher. To see at what AT #1 temp it does flow. I'll then add 1/4 plus what I think low. Through return hose, with my larger syringe.
if over, in the 98-03. I hook my hose to catch can back up. Start and stop engine in 1 second. One can also; either disconnect ATF cooler hose from bottom of engine radiator, to drain off a tad. But that usually involves remove skid plate, which I don't for AT flushes.
BTW: A really good transmission shop. Suggest over filling a tad. We're are better over than under. To this end, I set level at very lowest temp range recommended or few f degrees, lower than minimum range.
that brings up another question lol. if you are setting to the lower range of 97f, if it's low then wouldn't you want to immediately add more atf, rather than getting the AT up to 100,105,110, 115+? in other words, wouldn't warming up the AT (further than 97f) give you a false level of atf?
He wants to understand how low it is so he can roughly calc how much to add instead or blindly adding 3 quarts.
i should've said in 04+ bc overfilling is not an issue in those since there is a check plug.
also, if you have to wait until 115 for fluid to come out of the check plug, what does that tell you? you're low by how much? that's why i think it makes sense to add atf right away if nothing comes out of the check plug at 97f.
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- #57
Not really. Remember I know how much out an in, which I started by draining the pan. So I know pan wasn't dry. I also add extra 1/2 qt. If so low I don't see flow out straw at 97 to 115F. It was low long before it came to me, and placed under a lot more load, than sitting in my shop idling. Also I'm not driving sloshes ATF to one side or end during turns and hills.
In 04-up 97F min - 115F max, is level set range. IIRC it's about 1/3 qt. from min to max.
ok @2001LC I followed your instructions and all went well EXCEPT:
1. when I drained the pain, I only got 2 qts instead of 3ish.
2. when I was satisfied I had drained all the old fluid, my drained amount totaled 10 qts, not 12 qts (obviously bc of the pan)
3. i still put 12.5 qts of fresh fluid in, however, thinking that mine was just grossly underfilled
4. when i got the AT to 97 degrees (verified by techstream), i opened the check plug and 2 whole qts came out. i had to shut off the engine so my drain bucket didn't overflow. when I started the engine back up, AT was at 100 and I opened the check plug again... not a drop came out.
5. thinking i somehow did something wrong, i pumped that 2 qts back into the fill port and tried again (we're back to 12.5 qts in)
6. this time i let the AT get to 104 and then i removed the check plug. once again, 2 whole qts came out, but this time i actually got to see the drain stream turn into a dribble.
all this to say, if your write-up was titled "full 10 qt flush" i would be perfectly satisfied, but since it's 12 qts, I am still wondering what went wrong. maybe my check "straw" is bent? or techstream is not showing a realtime AT fluid temp?
bottom line is i got 10 qts out and put 10 qts in so i am going to drive it as if all is well. pls let me know your thoughts!
1. when I drained the pain, I only got 2 qts instead of 3ish.
2. when I was satisfied I had drained all the old fluid, my drained amount totaled 10 qts, not 12 qts (obviously bc of the pan)
3. i still put 12.5 qts of fresh fluid in, however, thinking that mine was just grossly underfilled
4. when i got the AT to 97 degrees (verified by techstream), i opened the check plug and 2 whole qts came out. i had to shut off the engine so my drain bucket didn't overflow. when I started the engine back up, AT was at 100 and I opened the check plug again... not a drop came out.
5. thinking i somehow did something wrong, i pumped that 2 qts back into the fill port and tried again (we're back to 12.5 qts in)
6. this time i let the AT get to 104 and then i removed the check plug. once again, 2 whole qts came out, but this time i actually got to see the drain stream turn into a dribble.
all this to say, if your write-up was titled "full 10 qt flush" i would be perfectly satisfied, but since it's 12 qts, I am still wondering what went wrong. maybe my check "straw" is bent? or techstream is not showing a realtime AT fluid temp?
bottom line is i got 10 qts out and put 10 qts in so i am going to drive it as if all is well. pls let me know your thoughts!
i put a level on my frame before i started and it looked dead level. i did put the AHC in high so i could have more working room under the truck - maybe that have affected it. should i find a garage to park in and try again?
do you think it's safe to drive it right now?
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