best way to flush trannie fluid?

Status
Not open for further replies.
Joined
Sep 14, 2002
Messages
1,902
Location
cali
i am going to a transmission service on my accord 91...i am going to go and use OEM in my auto grannie.....dextron is kinda ruff on shifts...well i know how to drain and fill it, i am giong to run the car for a while so that the fluid gets a little warmer...but i want to get at least 95 percent of the older fluid out. i want to do this without using transmission flush additives or liquids. i am worried that it may hurt my seals or cause more wear if i do have a problem. i want the fluid from the back of the transmission and the torque converter to be pretty new..sicne i am trying to limit the mixture of both ATFs...

should i pull out one of my transmission cooler lines to the radiator and flush it that way and just keep adding fluid?

thanks guys..
 
I don't know the specifics of your car so hopefully someone who does will step in and give some specifics.

First off, drainin with a line disconnected and running the engine while adding fluid up top is a bad recipe IMO. Too much chance of something going wrong and starving the transmission.

If your torque converter has a drain plug you can get almost 95% of the old fluid out as long as you actually drop your transmission pan. And as for the fluid left in the lines...don't use an air gun to try to force it out unless you know it can be done safely. Some manufacturers have delicate checkballs and thin wall tubing in coolers that will break if too much pressure is applied.

Finally, the easiest way (just more expensive) is to bring it to a garage and have them do it with a special machine...can get over 99% out.

Just my 2 cents!

Mikie
 
thanks for replying. well that theroy of mine where i keep filling the trannie was a very scary thing..i dont feel like doing that...i dont think i have a drain bolt on my torque converter and in no way i will drop my pan...actually i dont have a pan...hehe i just have a plug. the trannie is a very small portion about the same size as my oil pan...i just want the majority of the fluid out...maybe i can drain it, fill it then run it then drain it again...kinda a waste though dont u think...i can use a vacumn hu...**** i have to find one...
 
On most transmissions you will find you only get about 60 to 75% out by dropping the pan, as the rest stays in the torque converter. I have always pulled the line at the radiator and added with no problems or scares. I figure this trick out one day when the hose broke and showered the engine with ATF+3 in my GCL. It pumped out 3.5 of it's 4.2 qts before I saw the smoke in my mirror and could stop from 80 mph.
I do the same for power steering pumps.
 
Doesn't that Honda have a small capacity transmission? If so, a couple of pan drains will change most of the fluid.

Otherwise, you'll have no problem with draining the pan and refilling, then remove one of the cooler hoses, extend it into a jug, run the engine to pump out one quart, stop the engine & refill that quart, pump out one more quart, etc., etc. To find the correct hose to disconnect, take one hose loose, disable the engine so it won't run, crank the engine and note the direction of ATF flow out that loose hose. I like to use the hose out of the cooler if it can be reached.

Do consider either using Auto-Rx or 131-Neutra for gently cleaning your transmission over a 500 mile period. Contact Bob for the Neutra cleaning instructions. Also add an in-line Magnefine filter after the flush.

Ken

[ December 29, 2002, 02:33 PM: Message edited by: Ken2 ]
 
u know come to think of it, i dont have a pain for my trannie...well i remember the tech at honda telling me if the trannie is a full drain then it requires 7 quarts of oil, yet if its only a drain and full its like less than 4 quarts.

im kinda iffy on that cleaner stuff...iono just what i read in some forums that if u use a cleaner then the seals that may rupture sooner or later will rupture much fasater. hehe also if i were to use a cleaner, i would want one off the shelves, i cant stand online purchases..

what is a in-line Magnefine filter? man i wish i can change my filter, i dont have one.....only a screen.

thanks for replying by the way...
 
Doesn't your '91 Honda take Dexron II or III ATF? Buy any good brand of Dexron III ATF.

There's a big difference in the action of the 15 minute flush products and the 500-to-1000 mile flush products. You're right, do not use the 15 minute products, but do consider the gentle 500 mile products.
http://www.auto-rx.net

Here's the Magnefine filter...many autoparts stores sell them; I've seen them repackaged under other labels--just ask for the in-line transmission filter, preferably with the internal magnet, and I think your car uses the 3/8" size.
http://www.emergingent.com/subpage1Magnefine.htm

Ken
 
thanks for the links...my car does take dextron II/III. but i notice that OEM honda is alot smoother in shifting. with my 157k miles on this car and my harsh automatic shifting i think my trannie deserves to have some good fluid...unless u know of ne other brand that is good that i can try..
 
IMO you should use Amsoil universal synthetic ATF. That stuff alone solved alot of my problems. It is a bit pricey but worth every penny.

Now, for your drain dillema. I didn't realize you had such a small capacity and no drain plug for the TC. Ok, you're saying that completely empty it takes 7 quarts. A drain will yield 4 quarts. So, once you drain it and add new fluid you'll see a percentage of new to old fluid at 57%/43%. Do another drain after running the engine for a little while. Assuming that it has been thoroughly mixed when you drain 4 quarts 43% of that drain is old fluid. 43% of 4 is 1.72 quarts. Refill with new. You now have 1.28 quarts of old fluid to 5.72 quarts of new, or 82%/18% new to old. If you do one more drain you will end up with a final ratio of 92%/8%. That's fairly close to what you wanted and it only involved three drains and 12 quarts of fluid.

The "drain a quart and add a quart" method will also work, but only do this if you are careful to not get carried away and try to drain too much. When I was young and stupid (now I'm just old and stupid) I drained too much and burn up my transmission.

Good luck to ya!

Mikie
 
sounds like a good idea as well, though im using more money but my goal is to get mostly new fluid in there..perhaps not now i will not try amsoil, but maybe in the next change i will..right now im using my money for my cars detailing..im buying alot of products so i can clean up my car (yearly thing) hehe. thanks for the advice..
 
i tried to do it todayu....didnt work!! i couldnt get the bolt off...well i couldnt get the bolt off!!! i sprayed lubricant on there and it still wont budge...gosh i hope its not crossthreaded....i even used the power of my impact wrench (i went counter clockwise) to try and get it out and it only budged a little. i tried for like 20 minutes and no luck...i bet its because i didnt put any anti seis on the part where the bolt comes in contact with the trannie...its probably stuck right there...****it, now wut do i do...i never had this problem before...i may just get honda to do it and see if they can take it off but then if its crossthreaded then its going to need a new housing...i didnt even put it on that tight before, only at 30 pound torque....and it went on fine...err...i warmed up the engine as well...help dudes
 
Just currious... did you ever get that bolt off..???
confused.gif

Because when the weather get a little more berable...I am thinking of adding a magnet to the oil plug on my '02 Acura.
Jean

[ February 27, 2003, 08:56 AM: Message edited by: 2K2AcuraTL ]
 
quote:

Originally posted by 2K2AcuraTL:
Just currious... did you ever get that bolt off..???
confused.gif

Because when the weather get a little more berable...I am thinking of adding a magnet to the oil plug on my '02 Acura.
Jean


Pretty tight eh...I just did a manual transmission on a Honda Civic for a customer..the fill plug (where I always start)was on tight.Put a long bar on the rachet and bounce the bar counter-clockwise...it'll come off
grin.gif
...I use pipe sealant on the threads after this procedure...for next time.
 
digitaldrifter91, when I changed out my 1996 Accord's ATF at 20,000 miles, I just repeatedly drained, refilled, drove ~10 miles, and began again. (I didn't even bother using the new drain plug washer I bought ahead of time - it never leaked a drop with the old one.) I noticed my neighbor's new 2003 Accord owner's manual recommends that procedure three times for do-it-yourselfers. I did it eight times since I wasn't sure. (I guess I probably got all the old fluid out...) I was also using el cheapo SuperTech Dexron III. I realize that your car's out of warranty, but I've come 'round to the notion that if Honda (or any car make for that matter) recommends a specific fluid, go with that fluid - and that goes DOUBLE if the car's still under warranty. You're right - Dexron's acceptable according to Honda, but the shift quality is harsher unless you use something like Lubegard Black with Dexron III. I did just that, the shift quality was exceptionally smooth, but I'm no longer convinced about the wisdom of that decision. The car was totaled about 8,000 miles later, so I have no really long term experience with the Lubegard. Frankly, if you can get the Honda fluid for around $3.00/qt. as some have stated, THAT's as cheap as you're gonna get away with, it's the right stuff, and you won't have to worry whether 10,000 miles down the road your seals magically turn into sieves.

[ February 27, 2003, 08:34 PM: Message edited by: Ray H ]
 
If you change your auto transmission fluid on a Honda every 30,000 miles, it's a total waste to do anything more than a simple 1X drain and fill. Worrying about what's still in the torque converter is overly compulsive. Honda's transmissions have gears and clutches, nothing else.

I bought and older Honda this past year, and had no idea what the fluid service was like for the 137,000 miles on the ODO. So I changed the fluid a total of three times over the course of several months, to give plenty of time for the old stuff to completely mingle with the new stuff in between changes. Since changing the fluid gets rid of half of the capacity (in a Honda) I figure I have only about 12% of the original stuff left in there. That's not much.

Honda only recommends a 3X in a row "flush" if the system has become contaminated with non-recommended products. The normal service is 1X every 30,000 miles, under severe service.

P.S. Use Honda ATF-Z1, it's really smooth stuff!

[ February 27, 2003, 09:14 PM: Message edited by: S2000driver ]
 
quote:

Originally posted by 2K2AcuraTL:
I am thinking of adding a magnet to the oil plug on my '02 Acura.
Jean


Honda transmissions already have a magnet up closer to where the circulation is. It won't hurt to add another, but make sure the quality of the aftermarket bolt is as good as OEM.
 
quote:

Originally posted by S2000driver:

quote:

Originally posted by 2K2AcuraTL:
I am thinking of adding a magnet to the oil plug on my '02 Acura.
Jean


Honda transmissions already have a magnet up closer to where the circulation is. It won't hurt to add another, but make sure the quality of the aftermarket bolt is as good as OEM.


Actualy I will be adding a magnet TO the OEM bolt.
Basicaly a cylinder 0.25" OD x 0.50" in lenght and just placing it to the bolt. And these suckers are strong..
Just looking for a little more protection/insurance/peace of mind due to the Acura transmission problems...
mad.gif


[ February 27, 2003, 10:21 PM: Message edited by: 2K2AcuraTL ]
 
Here's a thought, how about draining the transmission pan, topping up and run the car at idle but in gear for 5-10mins then repeat the draining again?

After 2-3 times the transmission should have at least 80-90% fresh ATF?
 
quote:

Originally posted by gavinl:
Here's a thought, how about draining the transmission pan, topping up and run the car at idle but in gear for 5-10mins then repeat the draining again?

After 2-3 times the transmission should have at least 80-90% fresh ATF?


That is what I had thought of doing. If you just
keep topping it off then by the time you get it
done then 80%-90% of it should be clean right ?
Not only that but you haven't risked doing any damage to you car by running the OLE' FLUID IN A
BUCKET TRICK. It may cost a little more but be
safer. In this kind of situation I think it
would be funny to ask who invests in stocks and
who invests in mutual funds. DARING vs. SAFE.
rolleyes.gif
...........
grin.gif


Slade
 
Status
Not open for further replies.
Back
Top Bottom