Transmission flush or drain?

You don't need to run the transmission to purge the old fluid (unless you're doing a "poor man's machine flush") You just need to drain the pan and fill it up then run the trans for a min or two and repeat. You don't need to bleed the system in any way, I also would not recommend running a transmission with very low or no fluid in it (hence why you can't drain the torque converter from the oil pan as it could potentionally cause issues should you accidentally run it with no fluid.)

BlackWorksInc -- any downside to doing the "poor man's machine flush" -- i.e. using the transmission to pump old fluid out, then pouring in new fluid until you see fresh fluid coming out? I did this on our '05 Tacoma, which has the same engine/transmission as our '08 4Runner, and it seemed to work fine. I did the same as what gsrthomas did:

To flush the transmission I removed the return line that goes to the radiator. Started engine, let it run for 15 seconds or so to get out 2.5-3 quarts. Stopped engine, put in the same amount of fresh WS fluid into the transmission that came out. Repeated this 3-4 times until clean fluid was seen.
 
I bought one of these small drill pumps yrs ago with the "briggs" name for about $10. Damn' self propelled mower drain plug is a hassle to get to so briggs sold these to stick into the oil tubes and siphon oil to change it. As it turned out, its one of the best cheap tool purchase's I made as I have used it everywere. Anytime I need to move fluids I grab this and go.

It empties my mower in about a minute or less and it gets into tight places like manual trans,rearends,radiators,ect..real easy. Ive used it well over 8yrs now every fall on mower and alot in between.
I'd say its a perfect fit here to fill a sealed Toyota tranny with if you can locate a decent one.
They are cheap, Id try to get one with the hard plastic pvc hose kit but they sell pumps alone, pvc hose is about 3/8 - 1/2 in dia. about 2ft long as its great to stick down inside tight spots. Hose/pump kit may seal easier? Ive seen them under many different names at home stores but no briggs so?? They are in the sump pump area I think but could be anywere in home stores?

They "must" have a tight seal around the hose/pump/fitting area's or they suck air and fail to prime. Briggs seals good but while searching for image I just read some reviews saying some others are crap but Im sure they are just not sealing? That is a must for them to work I learned!
The larger soft hose can be stuck into a jug,tub, bucket ect.. then the small PVC hose goes into the trans or visa versa if needed. They can only pump one direction so you must unscrew the hose's and switch them to change directions of filling/draining? I read some saying direction arrows may be marked wrong, my briggs was marked right.
Heres one similar to mine [Dayton 3yu62]. I saw cheaper ones, but Daytons known for higher quality, at one time anyway? Who knows now? A good one is a fantastic freind, just never suck up gas or anything that a drill spark may blow you up...That might suck a little bit?...lol :crazy:

Dayton?
DAYTON Pump, Drill Driven Kit - G3378864 at Zoro
 
Performed a transmission fluid flush on my 06 sealed transmission last night. I had done a drain and fill a few months ago but determined I needed to do a complete flush due to the fact that I suspected the previous owner had the transmission fluid replaced at a shop. I don't think they used Toyota WS Fluid... So I needed to exchange all of the fluid. I drained the pan (4 quarts) and then disconnected the cooler line in front to do 2 quarts at a time turning the car on and off every 20-30 seconds. Total of 15 quarts. I used a bucket with the quarts lines marked on it. Once complete I did the level check by shorting the OBDII port. Drove it around for a few minutes working through all the gears and did another level check. The fluid that came out was a reddish brown and not very translucent. The fluid in there now is brand new Toyota WS fluid. My fill bolt on the transmission was really stuck on there. Had to use a 15/16th bolt extractor and a pipe to get it off. Replaced the bolt with a new 24mm bolt from the dealer. I feel better knowing that it is now good to go for several years... and the next time I service it I will only do a drain and fill from the pan.

This was the 3rd time I have done a fluid flush by using the return line. I have never had an issue with this method.
 
A quick note of what happens in your transmission, the fluid holds the duty of being a friction enhancer, lubricant, coolant, and hydraulic fluid. Over time small bits of the metal clutch discs and the friction material wear off, mixing with the fluid and turning into deposits on the inside of the transmission like you would find with clogging drains in a house.

When you perform a fluid flush you are often using a machine to force fluid through the system, our unit uses the transmission itself, but often those pressures can loosen deposits. You see this more with a "backflow" method that provides pressure against normal flow to break off deposits.

But in both cases it can loosen a large amount of deposits that can clog up the filter and or the valve body of the transmission impeding proper operation. That's why for transmissions that have not been serviced in 90k are often not flushed.

So [MENTION=66389]BlackWorksInc[/MENTION] , I have posted a question about the tranny fluid temp check mode in this thread, and I would love to have your thoughts on the matter (or anyone else's thoughts if you know the answer), if you have time to weigh in.

Sincerely,

-Phil
 
Anyone feel free to chime in, I'd love to hear from some of T4R's elite members and Toyota techs especially.

[Background info] I bought a 2004 V8 SR5 a year ago with 175,000 miles on the clock. It's served me well for the last 17,000 miles with regular oil changes, a spark plug change and no issues otherwise--honestly for the mileage I'm amazed I haven't had any other issues.

I've been itching to do a fluid change on the front and rear diffs, the transfer case, and transmission lately just for peace of mind. Upon looking through receipts from the previous owner I found the last recorded trans flush and fluid change for the front/rear diffs and T-case were at 114,000 and according to the receipt Dexron III was used in the transmission. It currently doesn't have any transmission issues aside from a slightly harder shift than when I bought it.

I guess I'm just curious as to what I should do here--I've bought some Toyota WS fluid already, having assumed it was WS in the transmission, but I can't find if it is safe to combine with Dexron III, obviously my gut tells me it won't. Which leads me to think a flush is in order, however at 192,000 miles I get the impression most would just do a few cycles of drain and fill for obvious reasons.
I was hoping to just do a standard drain and fill with Toyota WS, but I'm starting to think I should just take it to the dealer and have them flush it to avoid any compatibility issues and so I know it's been done since I don't have any record of it having been changed or flushed for the last 78,000 miles.

What are your thoughts? :shrug:
 
My 2006 4.0L 4Runner has 33,000 miles on it and I've noticed it will "slip" when I'm rolling in seemingly neutral before applying throttle and then it catches and grabs back into gear...almost as though it leaves it in neutral too long and then clicks back into gear late after I press the throttle. It shifts fine in all other conditions, so I don't suspect any issues with the actual transmission. My question as it relates to this thread is: with a vehicle that is 10 years old and with that low miles, should I drain and refill the trans because the fluid would have sat a lot and maybe collected condensation which would have diluted the fluid. I've read this is a definite issue with vehicles that have sat.

Anyone think the shifting issue (which is hard to replicate but happens in specific situations like I described above) would be helped or fixed by changing? Would I be just as well leaving it be until 90,000 miles or whenever it needs to be changed officially?
 
My 2006 4.0L 4Runner has 33,000 miles on it and I've noticed it will "slip" when I'm rolling in seemingly neutral before applying throttle and then it catches and grabs back into gear...almost as though it leaves it in neutral too long and then clicks back into gear late after I press the throttle. It shifts fine in all other conditions, so I don't suspect any issues with the actual transmission. My question as it relates to this thread is: with a vehicle that is 10 years old and with that low miles, should I drain and refill the trans because the fluid would have sat a lot and maybe collected condensation which would have diluted the fluid. I've read this is a definite issue with vehicles that have sat.

Anyone think the shifting issue (which is hard to replicate but happens in specific situations like I described above) would be helped or fixed by changing? Would I be just as well leaving it be until 90,000 miles or whenever it needs to be changed officially?

Drain and Fill would be a cheap experiment to see if it helps/fixes the issue.
If it's not working well now, I'd do it asap--certainly not leaving it until 90,000 miles.
 
this poor man's machine flush is the best thing you can do than just draining/ refilling it. with this, you know that all your fluid are new and not mixed with 9 Qts of old fluid and 4 quarts of new fluid.

that's what I did on my transmission, the poor man's flush. :) I saved a lot and at the same time, the transmission's life is extended. sounds right to me. :)

BlackWorksInc -- any downside to doing the "poor man's machine flush" -- i.e. using the transmission to pump old fluid out, then pouring in new fluid until you see fresh fluid coming out? I did this on our '05 Tacoma, which has the same engine/transmission as our '08 4Runner, and it seemed to work fine. I did the same as what gsrthomas did:
 
Boy I messed up big time on this one! i accidentally drained my tran fluid on my 2003 Limited 4Runner when trying to change the oil :help: :help::help:
I replaced the fluids that i lost with T4 tran fluid and cannot figure out if i got the level right. It seems to not lower its levels when the engine is cold or hot. I believe i need to drain some. I took it to my mechanic and the dealer and another friend. I had two of them tell me its fine my mechanic said its high and not good should be drained to proper level.

Any advice?
 
Boy I messed up big time on this one! i accidentally drained my tran fluid on my 2003 Limited 4Runner when trying to change the oil :help: :help::help:
I replaced the fluids that i lost with T4 tran fluid and cannot figure out if i got the level right. It seems to not lower its levels when the engine is cold or hot. I believe i need to drain some. I took it to my mechanic and the dealer and another friend. I had two of them tell me its fine my mechanic said its high and not good should be drained to proper level.

Any advice?

Yes, go here:
https://www.tacomaworld.com/threads/how-to-drain-refill-automatic-transmission.63851/page-34
 
Can anyone confirm that the drain procedure using the "AT temp" check light on the dash works on a 4.0 V6 2wd ? I ask because this light does NOT light up when I turn the key on before starting the engine. thanks!
 
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Can anyone confirm that the drain procedure using the "atm temp" light works on a 4.0 V6 2wd ? I ask because this light does NOT light up when I turn the key on before starting the engine. thanks!

NO! it must be at temp. there are a lot of threads on this. I'll pull them up in a second. but in mean time did you disregard the amount you drained? if put what you drained a old oil container you can guestmate how much you lost and put the same amount back in. easiest way.


https://www.youtube.com/watch?v=cNcecuGzTDg

http://www.toyota-4runner.org/4th-gen-t4rs/195074-atf-exchange-using-cooling-line.html

edit btw use toyota fluid, if its WS use that from dealer.

sec there is one for 4runners finding it.
 
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Drain & fill. Transmissions are very picky on having them flushed. Power steering is your choice and synthetic is too. I use synthetic myself personally.
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Can anyone confirm that the drain procedure using the "AT temp" check light on the dash works on a 4.0 V6 2wd ? I ask because this light does NOT light up when I turn the key on before starting the engine. thanks!

you can get a scan gauge. measure the ATF Temp. when it is in range. read it, then it should be at the right level. :)
 
NO! it must be at temp. there are a lot of threads on this. I'll pull them up in a second. but in mean time did you disregard the amount you drained? if put what you drained a old oil container you can guestmate how much you lost and put the same amount back in. easiest way.


https://www.youtube.com/watch?v=cNcecuGzTDg

http://www.toyota-4runner.org/4th-gen-t4rs/195074-atf-exchange-using-cooling-line.html

edit btw use toyota fluid, if its WS use that from dealer.

sec there is one for 4runners finding it.

Yeah but if you are like me and you are clumsy, you spill some and you forget some and then your math is bad...
 
Yeah but if you are like me and you are clumsy, you spill some and you forget some and then your math is bad...

No one has posted here in a while but my 2006 4runner has about 149,000 miles and I don't believe the transmission fluid has ever been changed. I've replaced all other fluids though. I tend to relatively often when I come to a rolling stop and then press the gas it seems to stay in neutral for a second then move forward. Could this be caused by needing new fluid?
 
No one has posted here in a while but my 2006 4runner has about 149,000 miles and I don't believe the transmission fluid has ever been changed. I've replaced all other fluids though. I tend to relatively often when I come to a rolling stop and then press the gas it seems to stay in neutral for a second then move forward. Could this be caused by needing new fluid?

I don't know if just new fluid would solve this but it can't hurt anything and would be best for the transmission to flush the old fluid and put in new fluid epsecially if it has never been done.

That being said old fluid shouldn't cause the transmission to slip, BUT since the transmission may have never been seviced/fluid changed or even if it has it could very well be low on fluid and that indeed can cause the transmission to slip, so at the very least the fluid level should be properly checked to insure it's at the proper level.
 
I am opting to post this question on a "legacy thread" instead of starting a new one because the answer could clarify a lot of points within this thread.

The word "Flush" is being tossed around in a few different contexts here. I'd like to add the following to the discussion, and if I'm wrong, please educate me.

It was my understanding that a "Flush" involves some sort of pressurized machine that adds used a cleaning solvent, and the solvent and high pressure is what caused the problems for many transmissions.

There is also a method, sometimes called "Fluid Exchange" which also uses a machine of some sort, but is not pressurized and only trades old fluid for new.
This can also be done at home, the "run it for 15 seconds, replace what came out" method.

Then there is the "dilution" method where people drop the pan every other oil change and eventually this somehow changes all the fluid.
 
I don't know if just new fluid would solve this but it can't hurt anything and would be best for the transmission to flush the old fluid and put in new fluid epsecially if it has never been done.

That being said old fluid shouldn't cause the transmission to slip, BUT since the transmission may have never been seviced/fluid changed or even if it has it could very well be low on fluid and that indeed can cause the transmission to slip, so at the very least the fluid level should be properly checked to insure it's at the proper level.

Okay thanks for getting back to me. I'm going to see if there is a local shop or dealership that would be able to do it. At college so don't have my tools or time to do it myself.
 

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