Self flush auto trans? (89 GL coupe)

Discussion in 'General Motoring' started by Hachiroku ハチロク, Dec 18, 2008.

  1. OK, my tranny's really starting to bum me out. I checked the level again,
    added a *LITTLE*, and again it's puking from the breather hose.

    All of this started last week when I added some trans fluid to what
    appeared to be a tranny low on fluid.

    I thought I had replaced the screen, but now I'm not sure. I can't
    remember. I know I had this problem last year when I filled it to between
    Low and Full on the dipstick, and IIRC I dropped the pan and replaced the
    filter, but I just can't remember.

    Good news is, filter is $7.99 at AutoZone. Bad news is, they can't get

    I'm afraid I mixed different types of trans fluid. I use Castrol, and I
    usually use 'Domestic" since it is Dexron/Mercon, which I believe is
    recommended, but I can't remember!! I may have used the "Foreign" version,
    but when I filled the tranny I used "Domestic" which is wht I use in the

    The trans is in good shape except for the puking that began after the last
    fill, so I am thinking about flushing, something I am not really in favor
    of, but I want to get the 'mix' completely out of the trans.

    I called a place listed in the phone book. I don't know them personally
    but I know of them and they are good guys. He described a procdure to me
    that I have been thinking about, wondering if it would work, and that is
    using the pump in the transmission as a pump to flush the fluid. His
    answer confirmed that I'm not so dumb afterall, and is something like

    <NOTE: This is for a Chrysler 3-speed auto in an '85 Caravan>


    First, drain the fluid from the pan, just like you would using Mr.
    Macfairlane's procedure. Once you've replaced the filter, the pan gasket,
    and reinstalled the pan, you're ready for the next step.

    Fill the transmission to the proper level using the proper type of
    transmission fluid. Then disconnect the return transmission line (the line
    in which transmission fluid flows from the transmission cooler back to the
    transmission), located near the bottom of the radiator. There's two
    transmission lines connected in this location, and the bottom line is
    usually the return line. Once the line has been disconnected, attach a
    clear piece of tubing to the transmission cooler, the same diameter as the
    transmission line, approximately 5-6 feet long, using the transmission
    line clamp to secure it.

    Place the unattached end of the clear tube in a plastic, one gallon milk
    container and place it where it can be seen (like not under the car).

    For the next portion of the procedure, make sure that the parking brake is
    set prior to continuing. Start the engine. The transmission needs to be
    put into "Drive" so the torque converter fluid is changed as well. Some
    transmissions will only circulate fluid through the torque converter only
    in drive. This especially applies to the electronically controlled
    transmissions. [Craig Sherman noted that Drive is needed for most
    transmissions, based on technical manuals]

    After approximately 4 to 5 quarts (obviously, if it's more than 4 quarts,
    you'll have to turn of the engine, and fetch another milk jug) of fluid
    have been pumped out, you should notice a change in the color of the
    fluid. It should go from a brownish red color, to a bright pinkish red
    color. When this happens, all of the old fluid has been replaced with new

    Be careful not to overfill the tranny during this procedure.

    When completed, reconnect the transmission return line to the transmission
    cooler. Check the fluid level as you normally would, and add fluid as


    The guy I spoke to said to just fill the tranny's filler neck like you
    would when filling the transmission. When it starts to run clear red, stop
    filling and let it run until it starts to splutter and then stop and fill
    to normal level, drive the car until it reaches operating temperature and
    then check again and fill if required.

    Makes sense to me! What I was wondering is, what if you take one gallon
    jug empty to fill with the old fluid, and another full gallon (or more) to
    draw in fresh tranny fluid?

    Any ideas?

    BTW, I am NOT a fan of flushing, but I want to see if it resolves the
    Hachiroku ハチロク, Dec 18, 2008
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  2. Hachiroku ハチロク

    Tegger Guest

    It's foaming. That's what makes it spill out the breather.

    Foaming fluid is old fluid: the anti-foam agents have deteriorated.

    The best home remedy?
    1) Drain & fill.
    2) Drive.
    3) Drain & fill again.
    4) Repeat from #2 at least twice more.
    5) Dump old jalopy and buy new car with tranny that's been better cared

    But then again, maybe Subies have some quirks Toyotas haven't got...
    Tegger, Dec 19, 2008
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  3. (the tranny's the best thing on the didn't act up until I added
    ATF last week...)

    That's why I'm wondering if mixing different types of ATF is causing the

    As an aside...I threw in some Sea Foam. I know a guy who was a Suby tech
    for 15 years...he works on Jags and some pretty expensive exotics now, and
    he tipped me off to the Sea Foam...
    Hachiroku ハチロク, Dec 19, 2008
  4. Hachiroku ハチロク

    Tegger Guest


    Maybe the slushbox was already on the verge of foaming and all it took was
    just...a leeetle bit more.

    And I've heard rumblings that SeaFoam is made of snake-oil.

    Well, actually, it consists of camp stove fuel, rubbing alcohol and a light
    lubricating oil similar to that which is already present in ATF.
    (Gotta wonder what their margin is...)

    There is simply no substitute for regular fluid changes, those being done
    in the total absence of snake-oil additives.
    Tegger, Dec 19, 2008
  5. What makes it foam?
    A LOT!!!! Last one was $7.99, this one was $9.99!
    The transmission started working better almost right off the bat.

    Other than this little problem the trans was working GREAT before, and the
    trans fluid is the correct color and smell.
    Hachiroku ハチロク, Dec 19, 2008
  6. Hachiroku ハチロク

    Ray O Guest

    Sticking another hose in clean ATF to draw it into the transmission probably
    won't work because the transmission pushes the fluid through the radiator.

    When you messed with the filter, you did get it back in exactly the right
    position with no gaps between the filter and valve body, right?
    Ray O, Dec 19, 2008
  7. Always! I can't remember what I did, but that was back in January. The car
    ran great until last week when I added fluid.

    We're supposed to get tomorrow what you got today. No getting under the
    car for a few days...
    Hachiroku ハチロク, Dec 19, 2008
  8. Hachiroku ハチロク

    Ray O Guest

    It just started snowing in the last half hour. The weather guessers are
    saying between 2 and 12 inches - nothing like narrowing down the forecast!
    Ray O, Dec 19, 2008
  9. Hachiroku ハチロク

    Tegger Guest

    The anti-foaming additives wear out. That's one reason you need to
    replace all the fluid at regular intervals.

    I do a drain-and-fill several times a year on our Tercel, with a gallon
    out of the two in there coming out each time. This way I keep all the
    fluid mostly fresh most of the time, with the proportion of old fluid
    staying low compared to the volume of new.

    Then maybe SeaFoam contains magic snake oil that really works.
    Tegger, Dec 19, 2008
  10. WOW! It started snowing here about 2 hours after there. Must be a BIG

    They said it was a fast moving storm. It's 3PM EST now and we're getting
    Hachiroku ハチロク, Dec 19, 2008
  11. Hachiroku ハチロク

    Mike Hunter Guest

    The weather forecasters can't get it right when they tell us what will
    happen in two days yet the environut global warming theorists expect us to
    believe THEY can tell us what the weather will be like in FIFTY years if we
    don't chage our ways. I wish they could just explain how global warming
    led to it snowing in New Orleans and in the desert in and around Los Vegas
    recently LOL
    Mike Hunter, Dec 19, 2008
  12. Hachiroku ハチロク

    Ray O Guest

    I finally broke out the snow blower. I didn't do any of the stuff I tell
    everyone else to do so the oil is over a year old, the fuel was in the tank
    since last spring, and it fired right up. Now all I gotta do is tighten the
    auger drive belt so it quits squealing.
    Ray O, Dec 20, 2008
  13. We had 2" here the other day. I used the 'little boy' (30? year old Airens
    5HP in VG condition). Changed the oil before I put it in the garage. Put
    fresh gas in it when it ran out Wednesday!

    Tomorrow 'fat man' comes out. 30+ year old AMF 'Polar Bear' with a new
    Techumseh Snow King, 1 year old. Changed the oil before storing it.
    Started last week and runs good (it better!) Motor was $250 on eBay, brand

    We ended up with 4" here. They were estimating 8-12 at first, them moved
    it down one county, and revised us to 4-10.
    Hachiroku ハチロク, Dec 20, 2008
  14. You should know how to better think logically and detect fallacies in
    logic, especially your own. LOL.
    larry moe 'n curly, Dec 20, 2008
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