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Power Flush or change Transmission OIl

I have a 2005 Toyota Matrix with 53,000 miles. I had the transmission oil changed at 30,000 miles , and the last time I had it in for an oil change, the service writer told me I should have it power flushed since the oil change leaves too much of the old oil in the tranny. The oil looks clean and doesn't smell. Should I wait till 60 K and have it changed again, or have it flushed now? The owners manual says it should be changed at 60,000 , and doesn't mention anything about power flushing.


  • edited July 2009

    Just have the trans fluid (and filter, if so equipped) changed at 60k.

    A "flush" is not called for by the manufacturer, and if not done properly it can damage the transmission. It will definitely damage your wallet.
  • edited July 2009
    A few thoughts (though I'm sure you'll hear others).

    Those who push flushing are the ones with flushing machines that make nice profits.

    I haven't seen many, or any, manufacturer vehicle owner's manuals which specify flushing.

    Flushing doesn't remove the pan. Pan removal allows you to replace or clean the filter. It also allows you to remove the sediment that builds up at the bottom of the pan.

    If you have sediment in the bottom of your pan, flushing will "stir" it up, and increase the risk that a piece of sediment will get lodged in a valve body valve.

    I would consider flushing only if I knew the pan and filter were already clean, and I knew that the person flushing it used the exact trans fluid specified (instead of a generic fluid with additives added for your car). Since those conditions are very unlikely to occur, I tend to stay away from flushing.

  • edited July 2009
    They only want to flush the money from your wallet. BTW, automatic transmissions (what I assume you have) use fluid, manuals have oil. 30K miles is a good interval to change the fluid.
  • edited July 2009
    who did your 30,000 mile change? an independent or dealership. When in doubt follow your service maintenance schedule. Mt Toyota dealership has never deviated from the printed schedule.
  • edited July 2009
    Ask your service writer how the automatic transmission world possibly survived for decades prior to the invention of the power flush machine! He's right, a drop and drain doesn't get everything out, but it doesn't have to, unless your transmission is having a problem. It is no surprise that the dealer's pushing unneeded services, that's what stopped me from going to my Lexus dealer. The service writer insisted that the tranny fluid be changed every 15,000 miles!
  • edited July 2009
    It is difficult to say since the language in the owner manual seems to be ambiguous. ?Changed? is not very precise, but it is likely that it means a full replacement of the fluid. It is rare today, to find a torque converter that can be drained and if you can?t, you leave more than half the fluid in there. Even with a drain plug there is a lot left in there. Just dropping the trans pan and refilling is like paying off your credit card by making the minimum payment every month.

    The bet thing to do is use a machine or just pull the cooler line(s) and pump the fluid out. Then drop the pan, inspect it, clean it and change the filter. Put a 2-4 (depending on capacity) quarts of fluid in the trans through the fill tube and pump half of that out. You just flushed the transmission. Button everything up and refill.
  • edited July 2009
    If your transmission contains a serviceable filter, then "Power-Flushing" becomes a meaningless term, as it ignores the filter and focuses on your wallet...
  • edited July 2009
    The dealer did the 30K fluid change ( meant to say fluid before, not oil......)
  • edited July 2009
    Unless the fluid is contaminated, flushing is really not necessary. You did right by servicing the trans at 30k miles. You can wait for 60k and service it again. Drop pan and change filter and refill using Toyota fluid. Another reason to make sure the pan gets dropped is that the fluid in the pan is the dirtiest fluid in the transmission so it must be dropped and changed.

  • edited July 2009
    If that is his only reason and the manual doesn't say flush, don't have a flush done.
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