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It's faster, easier and cheaper to do the simple pan drain maintenance every 30K or so after a full fluid exchange. Once you get the original fluid out with all the break-in residue from the clutches and wear-in, it's not critical to do another complete flush. But, it won't hurt anything either so you can do it anyway you want. Jimmee recommended a full exchange early (like at 50-60K) and then a pan drain every 30-35 thereafter and that's what I've been doing. My "new" fluid was still bright red after having put 45K on it when I did the last pan drain. :smile

DEWFPO
Yep that's the plan. Keep your oil nice and red. :grin
 

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I have been doing a full flush every 50K. I checked the color of the fluid at 30K and its still red ( and that is 30K of up and down a 5500 ft mountain everyday) I may just do a drain and fill next time around. How much fluid is used for a drain and fill only? I`m being lazy and don't want to re read he entire thread :)
Depending on how hot the ATF is when you drain it, and how long you leave the drain plug out, it can be anywhere from 3.1 qts to 3.7 qts. So it's always more than 3 qts and always less than 4 qts.

DEWFPO
 

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So I just thought I'd throw this out here for more info, not sure how accurate it is, just what I was told from a trusted auto tech, but anyway, he said never to fully flush these transmissions. He said that debris and stuff which are stuck against the filter can be pushed back into the system and cause damage. He told me that he recommends dropping the pan to drain fluid, changing the filter, and filling it back up. I had thought I read that there wasn't a replaceable filter in the transmission pan which I told him and he said he thought there was and he thought he remembered changing them before when he worked on these trucks but he was going to check back and let me know. I know tons of people have used this method and had good results so I don't question the process or anything, just wanted to post up some different information for people to talk about.
 

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So I just thought I'd throw this out here for more info, not sure how accurate it is, just what I was told from a trusted auto tech, but anyway, he said never to fully flush these transmissions. He said that debris and stuff which are stuck against the filter can be pushed back into the system and cause damage. He told me that he recommends dropping the pan to drain fluid, changing the filter, and filling it back up. I had thought I read that there wasn't a replaceable filter in the transmission pan which I told him and he said he thought there was and he thought he remembered changing them before when he worked on these trucks but he was going to check back and let me know. I know tons of people have used this method and had good results so I don't question the process or anything, just wanted to post up some different information for people to talk about.
I think most all agree that "flushing" with a machine is not a good thing on a trans with high mileage and no maintenance. Complete "fluid exchange" is a similar but different procedure. The fluid exchange uses the transmission's own pump to exchange all the old fluid for new fluid in the same manner fluid is pumped normally. Flushing machines can sometimes use solvents and/or back-flushing to 'clean out' a transmission which can cause problems in well used transmissions. By now I think most all repair shops have learned some hard lessons on using a 'flushing' machine.

There is a replaceable filter in the trans but it's pretty much just a fine screen to keep troublesome particles out of the valve body passages. Unless you are having problems with the trans, you likely don't need to drop the pan and change the filter based on what others have said that have done it.

DEWFPO
 

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So I just thought I'd throw this out here for more info, not sure how accurate it is, just what I was told from a trusted auto tech, but anyway, he said never to fully flush these transmissions. He said that debris and stuff which are stuck against the filter can be pushed back into the system and cause damage. He told me that he recommends dropping the pan to drain fluid, changing the filter, and filling it back up. I had thought I read that there wasn't a replaceable filter in the transmission pan which I told him and he said he thought there was and he thought he remembered changing them before when he worked on these trucks but he was going to check back and let me know. I know tons of people have used this method and had good results so I don't question the process or anything, just wanted to post up some different information for people to talk about.
There is a difference between doing a fluid exchange and a flush which is a misnomer. We call a fluid exchange a flush but no additives are used. The machines rely on the transmission to provide the pressure to push the fluid out of the transmission and the machine just pumps in the same amount. There is no forcible pressure used in a "flush".

Many automotive technicians believe ith the statements you made above but the truth is doing a fluid exchange on a high mileage vehicle will not cause any damage and can only help the transmission and extend it's life. Old pre-1980 transmissions had the above problems with debris hidden, etc but with newer fluids and synthetics we just don't see this happening anymore.

Most automatic transmissions these days do have a paper type filter but the Toyota A750 transmission still uses an old fashion brass mesh screen. This screen never needs to be changed although many people do change it and many auto parts stores only sell a pan gasket with the filter screen. It doesn't hurt to change it but its not necessary. Thus it's not necessary to drop the pan although many people drop it just to see whats in there. :)
 

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I think most all agree that "flushing" with a machine is not a good thing on a trans with high mileage and no maintenance. Complete "fluid exchange" is a similar but different procedure. The fluid exchange uses the transmission's own pump to exchange all the old fluid for new fluid in the same manner fluid is pumped normally. Flushing machines can sometimes use solvents and/or back-flushing to 'clean out' a transmission which can cause problems in well used transmissions. By now I think most all repair shops have learned some hard lessons on using a 'flushing' machine.

There is a replaceable filter in the trans but it's pretty much just a fine screen to keep troublesome particles out of the valve body passages. Unless you are having problems with the trans, you likely don't need to drop the pan and change the filter based on what others have said that have done it.

DEWFPO
There is a difference between doing a fluid exchange and a flush which is a misnomer. We call a fluid exchange a flush but no additives are used. The machines rely on the transmission to provide the pressure to push the fluid out of the transmission and the machine just pumps in the same amount. There is no forcible pressure used in a "flush".

Many automotive technicians believe ith the statements you made above but the truth is doing a fluid exchange on a high mileage vehicle will not cause any damage and can only help the transmission and extend it's life. Old pre-1980 transmissions had the above problems with debris hidden, etc but with newer fluids and synthetics we just don't see this happening anymore.

Most automatic transmissions these days do have a paper type filter but the Toyota A750 transmission still uses an old fashion brass mesh screen. This screen never needs to be changed although many people do change it and many auto parts stores only sell a pan gasket with the filter screen. It doesn't hurt to change it but its not necessary. Thus it's not necessary to drop the pan although many people drop it just to see whats in there. :)
Thank you guys for the info! I guess I wasn't specific when I was talking to him referring to a flush rather than a fluid exchange. Now I'm a little torn on what to do, my truck has 93k miles on it and the AT fluid hasn't been changed that I can remember. I originally wanted to do the exchange, then the shop convinced me to do the drain and refill, now I'm back to thinking I should do the exchange. He told me he'd drain and refill for less than $100, would it really be worth it to spend 2 or 3 times more than that to fully exchange it? If you guys do think it needs the exchange I'll most likely end up doing it myself to save some money, just would rather not as its getting cold out and my garage is not heated..:frown
 

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Thank you guys for the info! I guess I wasn't specific when I was talking to him referring to a flush rather than a fluid exchange. Now I'm a little torn on what to do, my truck has 93k miles on it and the AT fluid hasn't been changed that I can remember. I originally wanted to do the exchange, then the shop convinced me to do the drain and refill, now I'm back to thinking I should do the exchange. He told me he'd drain and refill for less than $100, would it really be worth it to spend 2 or 3 times more than that to fully exchange it? If you guys do think it needs the exchange I'll most likely end up doing it myself to save some money, just would rather not as its getting cold out and my garage is not heated..:frown
Bottom line is to have nice pink fluid. If you have already done a drain and fill and the fluid looks pretty good just do another drain and fill. You are doing exactly the same thing as a fluid exchange. A fluid exchange is quicker but the results remain the same. 4 Drain and fills = 1 fluid exchange.
 

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Jimmiee,

I may have missed it, but what is the recommended interval for "drain & fill"?
I did a complete fluid exchange @ 70k. I'm coming up on 100k, was thinking a drain & fill every 30k would be suitable.

Thoughts on this?

Thanks
G
 

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Jimmiee,

I may have missed it, but what is the recommended interval for "drain & fill"?
I did a complete fluid exchange @ 70k. I'm coming up on 100k, was thinking a drain & fill every 30k would be suitable.

Thoughts on this?

Thanks
G
Yep, 30K is when I drain and fill my vehicles. I just did my Silverado last weekend as a matter of fact. :)
 

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2007 AT 137k
I have this clunking going from R-D and D-R... also shuddering and shifts hard sometimes on the highway, in stop and go traffic ill hit the gas and about a second later it clunks and jerks forward. Should I put new tranny fluid in and see if it helps or any ideas? thanks
I have 4 qts on hand should i do a quick drain and fill to see if it helps at all first? Dont feel like purchasing 160 bucks in fluid if it is not gonna help
 

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2007 AT 137k
I have this clunking going from R-D and D-R... also shuddering and shifts hard sometimes on the highway, in stop and go traffic ill hit the gas and about a second later it clunks and jerks forward. Should I put new tranny fluid in and see if it helps or any ideas? thanks
I have 4 qts on hand should i do a quick drain and fill to see if it helps at all first? Dont feel like purchasing 160 bucks in fluid if it is not gonna help
It sounds like your transmission may be low on fluid. I would check for leaks and check the fluid level. Also, check the transfer case level and make sure it's not overfull. The ATF may be transferring into the transfer case.
Then drain and fill. If the oil is really dark you may want to do a flush after the drain and fill.
 

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Here is a fun graph for you guys doing the pan dump and refill. I did the math to figure out what is the average age of the ATF (in Kmiles) vs Kmiles on the vehicle if you dumped 3.5Qts out every 15Kmiles and replaced it with new fluid. I'm assuming the total transmission capacity is 12Qts.

(I just figured out how to add a graph)
 

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Here is what I was thinking about this flush

1) do it with the engine stone cold so the ATF in the trans has not expanded and what goes in matches the volume of what comes out
2) once the flush is complete, leave the fill hose in the side of the transmission and remove the overfill plug and continue filling until the fluid spills out the over flow, assuming the fluid is at 115*F

Once the ATF starts flowing out the overflow, its done. Does this sound right? So long as the overflow is open, you cant overfill the transmission. Just dont surpass 130*F before capping off overfill plug.

Thx

BTW my new to me FJ has 205,000 miles and there is no record of either the ATF or spark plugs ever being changed. It concerns me.
 

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Here is what I was thinking about this flush

1) do it with the engine stone cold so the ATF in the trans has not expanded and what goes in matches the volume of what comes out
2) once the flush is complete, leave the fill hose in the side of the transmission and remove the overfill plug and continue filling until the fluid spills out the over flow, assuming the fluid is at 115*F

Once the ATF starts flowing out the overflow, its done. Does this sound right? So long as the overflow is open, you cant overfill the transmission. Just dont surpass 130*F before capping off overfill plug.

Thx

BTW my new to me FJ has 205,000 miles and there is no record of either the ATF or spark plugs ever being changed. It concerns me.
If you follow the correct procedure you don't have to worry about the volume you take out because you will be installing the correct amount of new fluid every time.

1.) You can do that but you won't get as much of the ATF out as you would when it's hot unless you let it drain for hours or overnight. There's really no need. See my statement above.

2.) The fluid should just dribble out of the overflow. Again, if you follow the instructions you have no worries.

If you PM me I can e-mail you the procedure I use and have documented. Just follow the steps and it only takes about a hour or less.

DEWFPO
 

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If you follow the correct procedure you don't have to worry about the volume you take out because you will be installing the correct amount of new fluid every time.

1.) You can do that but you won't get as much of the ATF out as you would when it's hot unless you let it drain for hours or overnight. There's really no need. See my statement above.

2.) The fluid should just dribble out of the overflow. Again, if you follow the instructions you have no worries.

If you PM me I can e-mail you the procedure I use and have documented. Just follow the steps and it only takes about a hour or less.

DEWFPO
I get it. But we are assuming there was the correct amount in there to start with. But I am planning to add a tranny cooler to the circuit and will need to get it right while the engine is running.

Is there any risk to topping off while its running using the 1/2" tubing? My plan is to run 11 Qts thru for flush and use the last Qt for topping off to the correct level.
 

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The manual says not to insert the hose more than 30mm or you risk getting it eat up by moving parts so I assume the answer is yes. Having said that I did my warm up and fluid checks "sealed"
 

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I get it. But we are assuming there was the correct amount in there to start with. But I am planning to add a tranny cooler to the circuit and will need to get it right while the engine is running.

Is there any risk to topping off while its running using the 1/2" tubing? My plan is to run 11 Qts thru for flush and use the last Qt for topping off to the correct level.
You don't have to assume anything. It doesn't matter how much is in there now.

You can estimate how much the cooler and lines will use by filling them up on the workbench and noting how many ounces are used. You then have an idea of how much more to add. Remember you are checking the ATF level with the engine running so the cooler and lines will be charged with ATF so the level in the pan will be set at the correct level with the engine running. When the engine is off of course the pan will be "technically" overfilled by the amount you added for the new cooler and lines but it doesn't matter and doesn't hurt anything.

I top off with the engine running. The only thing you have to be careful about is that you keep the fill tube away from the hot exhaust pipes and cat.

DEWFPO
 

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I did an entire fluid change at 80k.
Just accomplished a pan drain and fill at 106k
Fluid was still red.
Cooler is doing its job.
May drain and fill again after another 20k
 

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I just finished up the replacement of the ATF on my '07 FJC thanks to this thread.

I'm all about the most expedient way of doing tasks. In the end, I left the 1/2" fill tubing in the fill hole from start to finish. I drained out 3 qts from the pan and replaced 4 qts to be sure not to run dry. Then purged out 2 qts at a time using the engine until I used up 10 qts of my 12 qts case. Then shorted the OBD plug and set the system to temp mode. I then added 3/4 qt of the 11th qt intentionally over-filling the pan. Then started the engine and simply waited 25 minutes for the AT temp light to come on. Removed the fill level plug and let the overfilled ATF drain out and capped it off at a trickle. Done and done.

I will add the cooler in the springtime. I'm Just not motivated to pull apart the front end right now.

This may be a helpful video with me purging my Sienna transmission where you can see how slow the fluid ejects.

https://youtu.be/gBSHmAibf8E
 
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