Transmission flush or drain?

I decided to fully flush my transmission at 52k miles. Glad I did because the fluid did not look so great. I am the 2nd owner and when I bought the 4runner, it had a brake controlled installed in the car so wanted to change the fluid out ASAP. Wanted to do a full flush rather than a serial dilution.

I highly recommend people to fully flush their transmissions as these can go 200k+ miles easily when maintained well. I used 14-15 quarts of Toyota WS fluid.

I even dropped the pan. Pan is very easy to remove so I cleaned up all the magnets on the bottom inside the pan. You can see the little magnets in the pics. They collect tiny metal debris. Magnets had a very very small coating of film on them. This means transmission is healthy.

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.

Then I entered the transmission temperature check mode to properly check the fluid. This is the trickiest part for me since the instructions off the Tacoma forum did not work with my 2009 model year 4runner. So I paid the $10 bucks to get it from the Toyota TIS site. After that worked great.

Transmission performs flawlessly . Smooth shifts. Will be repeating this once more in 2 years or so.


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OK I'll just drain it and put fluid back in. So the pan holds about 3 quarts? And what about the drain plug? Does it require a new crush washer?

That's what's widely reported.

I got close to 4 and then slightly over 4 on two drains. The front of the truck was raised. Maybe that played a role. Anyway, expect 3 but be prepared for more. I didn't use a new washer. No problems.

An aspect I didn't mention is that the combination of external transmission cooler and V8 presumably makes the vehicle extra easy on fluid in a transmission that has shown itself to be extremely robust.
 
I decided to fully flush my transmission at 52k miles. Glad I did because the fluid did not look so great. I am the 2nd owner and when I bought the 4runner, it had a brake controlled installed in the car so wanted to change the fluid out ASAP. Wanted to do a full flush rather than a serial dilution.

I highly recommend people to fully flush their transmissions as these can go 200k+ miles easily when maintained well. I used 14-15 quarts of Toyota WS fluid.

I even dropped the pan. Pan is very easy to remove so I cleaned up all the magnets on the bottom inside the pan. You can see the little magnets in the pics. They collect tiny metal debris. Magnets had a very very small coating of film on them. This means transmission is healthy.

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.

Then I entered the transmission temperature check mode to properly check the fluid. This is the trickiest part for me since the instructions off the Tacoma forum did not work with my 2009 model year 4runner. So I paid the $10 bucks to get it from the Toyota TIS site. After that worked great.

Transmission performs flawlessly . Smooth shifts. Will be repeating this once more in 2 years or so.


photo5-4_zps3deb4105.jpg~original

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photo2-12_zpse0f7de29.jpg~original

photo1-11_zps4c503fed.jpg~original


You didn't have to put new gaskets on the pan, and what did you do exactly to "clean" the pan. My main concern is obviously not wanting to screw up anything in regards to my transmission?
 
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.

Where did u put the fluid back in?
 
The fluid should be changed around 90~100k regardless what Toyota (or any other manufactuer with these "lifetime" fluids) say. There is no such thing as a "Lifetime" fluid, ATF is the signle most hard working fluid in most modern vehicles. It has to perform multiple functions that are split up in a vehicle's engine; it acts as a lubricant, coolant, hydraulic fluid, friction modifier, and maintain all this longer than engine oil or coolant usually. If you check your owner's manual you will see that "severe use" requires you to replace the ATF at 60k followed by 30k inspection/change intervals. In short, don't believe the snakeoil BS about "lifetime ATF."

To fill the transmission up you actually pump fluid through the inspection port into the transmission.
 
You didn't have to put new gaskets on the pan, and what did you do exactly to "clean" the pan. My main concern is obviously not wanting to screw up anything in regards to my transmission?

I just wiped everything down with a cloth including the magnets inside, and put back the magnets in there original position in the groves of the pan. Then I sprayed the pan with some brake fluid that evaporates quickly so I don't have any oily residue when installing the new gasket.

I always put a new gasket when I drop any pan. Gasket is around $15 from the dealer.

This is purely optional. I will not drop the pan again as my magnets were very clean. Plus we have a metal screen transmission filter that does not have to be replaced. So no need to remove the pan at all.

Just do a drain/refill or an entire flush as once.

Where did u put the fluid back in?

Fill hole is on the right side of the transmission. Take a hand pump and fill the same amount of fluid you drained out.
 
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Good info! But what about the air in the system from running the vehicle to purge the old fluid? Is this an issue?

I'm not sure I follow you? 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.)
 
This probably sounds like a dumb question (and maybe it is) but since we don't have a dipstick, how do you know the transmission has the proper fluid level in it? I've seen people write that you just "put back in what you took out" but what if the amount originally in there wasn't actually correct? There should be some way to know for sure that you have the proper amount of fluid in there and you can stop putting in more....but what's the trick?
 
This probably sounds like a dumb question (and maybe it is) but since we don't have a dipstick, how do you know the transmission has the proper fluid level in it? I've seen people write that you just "put back in what you took out" but what if the amount originally in there wasn't actually correct? There should be some way to know for sure that you have the proper amount of fluid in there and you can stop putting in more....but what's the trick?

The official procedure requires a few chants and incantations as well as procuring some dried Aardvark liver.

You can either do that or overfill a little, drive around the block a few times, and then unscrew the overflow bolt (the one in the middle of the pan).

Hat tip :hatsoff: to SkylineGTRacer and BlackWorksInc from this page http://www.toyota-4runner.org/4th-g...ed-atf-pan-instead-oil-pan-3.html#post1271634
 
Sorry...something odd has been going on. When I hit "submit", my comments don't display. It just shows a blank entry. Weird...
 
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So anyway, I drained my pan. Stood on the receiver hitch and tried to get it all to run out. Truck was on as level of a surface as I could find. Then I put 3.5 quarts of fresh WS back in. Warmed it up and cycled through all the gears a couple of times. Pulled the "check" plug and fluid gushed out! Either I messed something up, or 3.5 quarts is way too much.

My fluid that came out looked horrible. It was brown and nasty!! I've got 105,000 on the clock...and apparently the technician who entered "change trans fluid" into the system at 97,000 for the previous owner did NOT change the fluid. Yuck. Guess I will start doing this job once a year until pink fluid is all that runs out.
 
So anyway, I drained my pan. Stood on the receiver hitch and tried to get it all to run out. Truck was on as level of a surface as I could find. Then I put 3.5 quarts of fresh WS back in. Warmed it up and cycled through all the gears a couple of times. Pulled the "check" plug and fluid gushed out! Either I messed something up, or 3.5 quarts is way too much.

My fluid that came out looked horrible. It was brown and nasty!! I've got 105,000 on the clock...and apparently the technician who entered "change trans fluid" into the system at 97,000 for the previous owner did NOT change the fluid. Yuck. Guess I will start doing this job once a year until pink fluid is all that runs out.

So 3.5 is too much, so if you went back to do it again, what would you change different about your procedure, and how difficult was it as I'm still a novice and hesitant to do anything in regards to my transmission?
 
So 3.5 is too much, so if you went back to do it again, what would you change different about your procedure, and how difficult was it as I'm still a novice and hesitant to do anything in regards to my transmission?

Well, technically you're supposed to use the A/T temp check procedure to make sure your fluid is inside the perfect temp. range when doing this. I didn't do that. At that range, the fluid would be around 125 degrees. I found that it is almost impossible to pull the plug on the bottom of the pan without getting it all over your hand/arm and if the fluid was at full temp. it would burn you. Plus...as fluid gets hot it expands a little. So if you pull the check plug with it hot more fluid will come out. So I kept my trans. warm...but not hot...and pulled the check plug. I'd rather have slightly too much fluid than not enough.

The $5 hand pump from the auto parts store was a MUST. That fill plug hole is very hard to get to. I recommend trying to fill the trans with the exhaust cool...because you have to reach around the cats and exhaust pipe.

Not a fun job at all, but doable with the right tools. Took me 1 hour start to finish. Maybe toward the end of summer I'll do it again and try to get more of the nasty brown fluid out. "Lifetime fluid"..yeah right. They should have given us a dipstick!
 
Not a fun job at all, but doable with the right tools. Took me 1 hour start to finish. Maybe toward the end of summer I'll do it again and try to get more of the nasty brown fluid out. "Lifetime fluid"..yeah right. They should have given us a dipstick!

No kidding! What a racket!

Mine just started the "speed bumpyness" going through 4th gear getting into 5th with 133K on the odo.

Brought it into my local Toyota dealership and they are telling me that doing a drain and fill is not going to fix it. So it would be best to wait and see if it gets worse. He did advise that I perform this action myself and save some coin to see if it fixes it. I was being quoted $300 for the flush.

So after seeing the pictures of pan off and all that good stuff I am just going to do it myself. With any luck I will be able to take care of it.

Good thread, I'll report back to see if it fixes my issue.
 
SO, I pulled the plug on my pan and did a ~4 quart change. I followed the FSM instruction of shorting the diagnostic plug, getting it up to temp, and all that business, which was pretty easy. Time consuming but easy enough to do.

Anyway my report is good. The one fluid exchange fixed my problem. It shifts like normal now. It took about 10 miles for it to go away. May have been the fluid making its way into the torque converter.

I did go and pick up another 4 quarts to perform this action one more time for good measure. Which I will be doing soon. However the fluid did look decent, but it had over a 130K on it.

One note about the fluid check drain plug portion of the FSM. It does flow out of there quickly at first if you put almost all of the 4 quarts back in. It does seem intimidating, but it is normal. It will drain itself down within 30 seconds or so and boom, your good to go.
 
In the interest of full disclosure regarding my post on the previous page, I've now done a total of 4 drains and fills.

Now that I've learned how to do it easily and know how easy fluid level checks are, I saw no reason to limit it to two.
 
my 03 V6

So I've been through the entire thread and I haven't seen anyone mention using one of the oil/lube shops, Great Canadian Oil Change up here, same as Jiffy Lube or Mr. Lube.
I asked the guy at the shop about getting the tran fluid done. He said they use a machine that flushes at a constant pressure but they do not use any chemicals in the flush.
I've got an 03 V6 with 170,000 kms and I don't know if it's every been done. I saw the fluid and it looks pretty dark. I don't do much towing, other than a sea doo occasionally.
Is it safe to have this type of "flush"?
 
So I've been through the entire thread and I haven't seen anyone mention using one of the oil/lube shops, Great Canadian Oil Change up here, same as Jiffy Lube or Mr. Lube.
I asked the guy at the shop about getting the tran fluid done. He said they use a machine that flushes at a constant pressure but they do not use any chemicals in the flush.
I've got an 03 V6 with 170,000 kms and I don't know if it's every been done. I saw the fluid and it looks pretty dark. I don't do much towing, other than a sea doo occasionally.
Is it safe to have this type of "flush"?

No. Drain and fill with that many miles.
 

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