Transmission fluid in coolant reservoir

Discussion in 'Transmission & Drive train' started by 2004XLT, Sep 12, 2017.


  1. 2004XLT

    2004XLT Full Access Members

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    Yesterday I changed my transmission fluid and filter. Drove it about 60 miles yesterday. Today I went to check the fluid level in the tranny and noticed the fluid was also in my coolant expansion tank. I'll obviously replace the radiator, but how likely is it that my transmission is not going to last? Although there was trans fluid in the coolant I didn't see coolant on the trans dipstick. I'm concerned that if the fluids mixed there should be coolant in the transmission as well.
     
  2. stamp11127

    stamp11127 Super Moderator Staff Member

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    The coolant will trash the transmission if it mixes. Don't drive it until the radiator is swapped.
    If it was mine I would change the transfer fluid as well.
     
  3. 2004XLT

    2004XLT Full Access Members

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    I won't be driving it till I have the new radiator installed. I'll flush the coolant, but what should I do about the trans fluid? Just drop the pan and refill or? There was about a half cup of trans fluid in the coolant reservoir. I opened the petcock on the rad and drained a little coolant but it was clean. Trans fluid level did not rise and is clean so I don't think they've mixed yet. How much coolant would kill a transmission?
     

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