3bears is going through that same thing. Backflow back to the radiator is stuck somewhere along the line. Aftermarket caps sometimes work and sometimes don't. Oem ones just work.
That color could be coolant or trans fluid. You'll have to figure that one out...Gang,
Sorry to say I don't think this is yet resolved.
I installed a new OEM radiator cap from the stealership and, unless the leak is residual, it seems the issue is ongoing.
I found a few drops of fluid underneath and followed it upward. Taking off the shroud, I see what appears to be coolant pooling directly below the radiator.
That color could be coolant or trans fluid. You'll have to figure that one out...
Oily and fishy smelling = trans fluid
Less oily and sickly sweet smelling = coolant
Could be a leaking clamp or a punctured radiator, etc.
-Charlie
I doubt it's the transmission cooler in the radiator. The stock transmission cooler is surrounded by coolant except for the two fittings on the bottom that are external to the radiator. If the transmission cooler were leaking you would have a strawberry milkshake going on in your transmission. Are you sure it's transmission fluid and not coolant?Resurfacing this thread as I'm afraid this is still not resolved
What I've done:
- Replaced radiator cap with OEM
- Removed tranny cooler and reconnected hoses
- Had tranny cooler pressure tested at a transmission shop - fully checked out, no leaks
I wiped everything down until there wasn't a drop of fluid anywhere, then waited a few days. Once again, there was a small puddle of fluid under the truck.
Tranny fluid seems to be pooling up at the base of the radiator where the stock cooler sits. I don't think the radiator is punctured since it's not coolant. There's no wetness anywhere above this spot nor along any hoses/clamps. The photos make it seem like it's pooling on the driver side but this is because of the driveway grading; I was previously parked in a different spot and it pooled on the other side.
Driver side (between fan shroud and radiator)
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Passenger side
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Is it fair to say the stock cooler is faulty? As I mentioned above, the radiator (OEM) is just over a year old and was installed by a trusted shop.
I doubt it's the transmission cooler in the radiator. The stock transmission cooler is surrounded by coolant except for the two fittings on the bottom that are external to the radiator. If the transmission cooler were leaking you would have a strawberry milkshake going on in your transmission. Are you sure it's transmission fluid and not coolant?
Like phattyduck said when coolant and transmission fluid mix it becomes milky and pink. Very similar to strawberry milk or milkshake. I agree with him that it is likely a radiator leak. In order for powersteering fluid to get on the radiator there it would have to spray on a lot of other surfaces in order to reach that so that's not very likely.Well... I decided to verify and now I'm not sure if I might have the abhorred milkshake.
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Top left is coolant, top right is ATF, and bottom is what's pooling up under the radiator. Coolant and ATF each have their characteristic smells; the fluid in question doesn't seem to have any particular smell.. does that mean the two fluids have mixed? Could it be any other fluid? FWIW, there were no other symptoms the last time I drove it a week or so ago. Shifting was butter smooth, etc. And, the radiator is brand new.
Thoughts?
Thanks - will check out.
Not sure if it's related, but the top and bottom radiator hoses are also flattened or "sucked in" when the truck's not running. Should I look to replace the radiator cap? The radiator itself was replaced less than 5k miles ago.
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