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Transmission fluid in antifreeze: what to do?

My friend is unemployed and has about $500 to his name. He discovered the car (a 2002 Dodge Neon with 137,000 miles) leaking antifreeze and transmission fluid on the street. Tried driving it around the block; it went into gear at first, but then locked up when he tried to put it in reverse when parking it. He opened up the radiator to find a mix of antifreeze and tranny fluid.
<br/> The car was towed to a friend's shop, but he doesn't do major work like trannies. At this point, he can either repair the radiator and refill fluids for $500, then perhaps find out the transmission is shot too, or what I think he should do is have it towed somewhere else where they can tell if the transmission is shot before replacing the radiator. Is this possible? Suggested courses of action? He needs the car to get to a job he was just offered and has been searching for for months. Thanks in advance!


  • edited October 2007
    P.S. Obviously it will take all his money (including credit on his credit cards) to do the radiator work, so he can't afford it if that turns out to be just the beginning; he would need to find another strategy. That's why the angst.
  • edited October 2007
    You have a leak between the rad and tranny cooler, you'll need to replace the rad at the very least.

    You'll also need to drain and flush the tranny and replace the tranny filter. You might be lucky and get away with just that.

    Worst case, water has blown the tranny valve block seals ~ that's probably a new tranny.
  • edited October 2007
    Actually, what happens when engine coolant gets into the transmission the coolant will destroy sealing rings and will cause the clutch and band friction material to come apart. It sounds as though the radiator will need to be replaced AND the transmission disassembled completely, vatted to clean all the coolant out of it and rebuilt. He's looking at around $2,000-$2,500 if he's lucky.

  • edited October 2007
    If it was me, and I was broke, I would replace the radiator as cheaply as possible (maybe used), replace the coolant, replace the tranny fluid and filter, and hope for the best.
  • edited October 2007
    How does this happen and what can you do to prevent it?
  • edited October 2007
    "How does this happen and what can you do to prevent it?"

    It happens if the transmission cooler (inside the radiator) leaks, letting the higher pressure coolant into the transmission fluid.
  • edited October 2007
    Examine the transmission dipstick carefully. Is there ANY SIGN of moisture or coolant in the transmission fluid?? If the answer is yes, then the car is totaled. Since the tranny "locked up", I doubt a fluid change will help.
  • edited October 2007
    I would not spend one dime on it at this point. Pull the transmission dipstick and examine the fluid. If it's blackened or resembles sour milk then you can figure the trans is trashed so the radiator is a non-issue at this point.

    Considering the coolant leak, there's a chance the locking up could be the engine either overheating or it has suffered a blown head gasket. Coolant can enter the combustion chamber(s) past a blown gasket and cause what is called "hydrolock".

    To prevent problems in the future, I would advise disconnecting the radiator trans fluid cooler completely and installing an aftermarket fluid cooler.
    These can be had cheap, they're easy to install, and worth their weight in gold. Not only do this eliminate more transmission fluid heat they also get totally rid of that leaking radiator cooler problem.
    You can get a fluid cooler for anywhere from 50-75 bucks and that's dirt cheap insurance is the way I look at it.

  • edited October 2007
    But there IS no transmission fluid. It all leaked out. Can't the tranny have locked up just because all the fluid leaked out while he was going around the block?
  • edited October 2007
    Yes it is possible the transmission is not working due to lack of fluid, I would not assume the transmission is ruined. If he wants to try to fix it he need to get rid of the leak and replace both the coolant and transmission fluid. No one can diagnose this over the internet, he either needs to attempt to repair it, have someone diagnose it in person, or give up on the car.
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