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Ed_Manifold's avatar
Ed_Manifold
Explorer
Feb 15, 2014

Yearly Service

Earlier this week I posted a question about radiator size and Brett referred me back to my manufactures. Freightliner could not help me because of limited staff due to the storms but Tiffin was able to help me with radiator quantity 381/2 quarts. My next question is about changing my Allyson fluid. When I install Transynd Synthetic ATF which will replace my Dexron 111 ATF. I don't think this change will completely replace all of the Dexron so how long should I run the new Transynd before I change it again so that the remainder of the Dexron will be flushed out. After I make that change the Transynd will be good for up to 100,000 miles although I am not sure of the time line? I typically drive approximately 3,000 miles a year. Gee I won't have to change it again until I'm 99 years old.
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  • hzjcm8's avatar
    hzjcm8
    Explorer
    Feb 15, 2014
    Ed Manifold wrote:

    My next question is about changing my Allyson fluid. When I install Transynd Synthetic ATF which will replace my Dexron 111 ATF. I don't think this change will completely replace all of the Dexron so how long should I run the new Transynd before I change it again so that the remainder of the Dexron will be flushed out.


    Ed,
    Here's the procedure that I recommend for everyone. I believe this is the best possible solution. You really want the old DEXRON-III gone as quickly as possible in order to get all the benefits of TranSynd. Any old DEXRON-III continues to thin out and, without knowledge of the current condition of the fluid, it's best to just do the back to back changeover.

    PROCEDURE:
    • Drain old transmission fluid
    • Change the filters (lube and main if transmission is 3000/4000 Series); spin-on (if transmission is 2000 Series)
    • Install fresh TranSynd and check that fluid is in "Cold" band on dipstick
    • Drive for 1/2 hour to warm and circulate the fluid
    • Drain mixture
    • Install fresh TranSynd and ensure that level is correct with transmission in Park, engine at idle and vehicle parked on level surface.


    I do recommend a fluid analysis once a year on the transmission to ensure against contamination. Hope this helps. Arch Hoagland asked me to give some input.
  • wolfe10's avatar
    wolfe10
    Explorer
    Feb 15, 2014
    Per Allison:

    With first drain and fill (with filters changed as well) with Transynd, the next change interval is the same as for Dexron III.

    The change after that goes to the "Transynd change interval".
  • Ivylog's avatar
    Ivylog
    Explorer III
    Feb 15, 2014
    Because of the ATF that you cannot easily get out of the torque converter and cooler lines, the mixture of ATF and TransS will only be good for 69,305 miles and 82 years old. :W Change the filters too and seriously you should be good for 50K miles.

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