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Trans cooler lines leaking

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Old Aug 25, 2019 | 08:44 PM
  #1  
SoCal-Bob's Avatar
SoCal-Bob
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Mountain Pass
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Trans cooler lines leaking

2004 Expedition 5.4

They are leaking at the radiator, both of them. I replaced the radiator a couple years ago, and shortly after replacing, we pulled the cooler lines out to do a tranny flush. After the trans was serviced, and the lines replaced into their position, it started leaking. It wasn’t a bad leak, just a drop or two here and there. Now it’s leaving a puddle everywhere I go, and I’m constantly adding fluid.

Down to the nitty gritty, has anyone successfully changed out the fittings going into the radiator? These, aren’t screw in fittings, they are quick disconnect fittings. I read somewhere that they are not to be removed and replaced, but yet they sell them at the parts store.

If you have successfully replaced these boogers, is there any special treatment I should know?
 
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Old Aug 26, 2019 | 10:55 PM
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Spaznaut's Avatar
Spaznaut
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From: NE Tennessee
Generally there is an o-ring in there that goes bad from the heat. Not sure if its replaceable or just to replace the whole fitting. My '99 doesn't have the cooler
 
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Old Aug 28, 2019 | 04:30 AM
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SoCal-Bob
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I’m pretty sure that O-ring is toast, but I don’t believe it is replaceable. I believe the fitting is replaceable, but I remember reading somewhere it was not a good idea. I would like to know why, but I think I’m gonna have to find out the hard way. Worst case scenario is I have to replace the radiator.
 
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Old Aug 28, 2019 | 01:08 PM
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R&T Babich's Avatar
R&T Babich
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From: Thousand Oaks, CA
Originally Posted by SoCal-Bob
I’m pretty sure that O-ring is toast, but I don’t believe it is replaceable. I believe the fitting is replaceable, but I remember reading somewhere it was not a good idea. I would like to know why, but I think I’m gonna have to find out the hard way. Worst case scenario is I have to replace the radiator.
Are you talking about the red O-ring on the backside of the fitting?
If so, why would that not be replaceable?
It looks like a hi-temp silicone O-ring, wouldn't be hard to find.
 
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Old Aug 29, 2019 | 09:03 AM
  #5  
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SoCal-Bob
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Originally Posted by R&T Babich
Are you talking about the red O-ring on the backside of the fitting?
If so, why would that not be replaceable?
It looks like a hi-temp silicone O-ring, wouldn't be hard to find.

I was asking about the entire fitting. It’s the inner seal that’s leaking.
 
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Old Aug 29, 2019 | 02:45 PM
  #6  
R&T Babich's Avatar
R&T Babich
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From: Thousand Oaks, CA
Originally Posted by SoCal-Bob
I was asking about the entire fitting. It’s the inner seal that’s leaking.
The fitting screws into the cooler.
Is the leak around the cooler fitting in the radiator tank wall?

 
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Old Aug 29, 2019 | 11:56 PM
  #7  
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SoCal-Bob
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It appears to be leaking from where the cooler lines go into the fittings. Like the inner seals of the quick disconnect are no good.
 
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