external trans cooler leak !

[lubbock guy]

i have noticed in the last few weeks a couple of drops of transmission fluid coming from my external trans cooler. the cooler is the original to my truck, has 102,000miles on it. trans mission was flushed at 70kmiles and both trans filter replaced then. so far the level of the trans fluid is normal, fluid color still looks new. the leak appears to run down lower cooler bracket on the drivers side. the cooler is 14inches tall.
i am at a loss as to WHY ? the cooler is leaking?
could one of these filters be clogging? causing a restriction, causing the leak?
I also had the Bullet Proof Diesel all aluminum radiator installed in my truck around 5k miles ago, i know there is a internal trans cooler in the radiator, but there does not appear to be any fluid leaking from the trans cooler radiator lines.

[lubbock guy]

bump bump bump bump bump

[ZMANN]

it happens .. it may have been compromised when the radiator was swapped? or found a rock / bad connection /hose ETC

you will likely need to pull some stuff off to gain accesses and verify
if it is the cooler and not a line it can likely be repaired ,,

this is not a common failure ,, even the 7.3 guys like to use these

and no a blocked filter would cause this leak it would actually bypass the cooler if it were plugged

[lubbock guy]

is there a special test to determine the cooler is the cause of the leak?

Originally Posted by ZMANN

it happens .. it may have been compromised when the radiator was swapped? or found a rock / bad connection /hose ETC

you will likely need to pull some stuff off to gain accesses and verify
if it is the cooler and not a line it can likely be repaired ,,

this is not a common failure ,, even the 7.3 guys like to use these

and no a blocked filter would cause this leak it would actually bypass the cooler if it were plugged

[ZMANN]

IDK if they can dye test and use a special light like they can with engine oil?

if your sure it's the cooler the radiator shop can find the leak when it's out of the truck ,, or just replace with new ,, never a used one

[DieselFab67]

External trans cooler....? Or the cooler in your radiator?

External could be a hose or the cooler itself.

If it's the internal cooler (radiator) it could be an o-ring.

[lubbock guy]

About 5,000miles ago i had the All Aluminum BPD radiator installed, two weeks ago i did the BPD oil and EGR cooler install, now i get a few drops of trans fluid dripping down the lower trans bracket on the drivers side of the truck, this is the external 14" tall trans cooler. I mean what the Hell ? I did not even touch the damn trans cooler when i did the BPD oil cooler, the trans cooler was short enough to not need the BPD trans re locate brackets. so far, trans fluid level is normal, and trans fluid temps are 160 to 170. Should i get someone to look at this or ignore it?

Originally Posted by DieselFab67

External trans cooler....? Or the cooler in your radiator?

External could be a hose or the cooler itself.

If it's the internal cooler (radiator) it could be an o-ring.

[DieselFab67]

It might be leaking from one of the transmission cooler lines. Sometimes just touching a rubber hose is enough to make them leak. Make sure you fix it though. Oil leaking there will attract dust and over time your intercooler, trans cooler, and radiator fins will start to plug with oily dirt.

[lubbock guy]

the cooler line has one of those metal tension type connectors. you think i should use a hose clamp to replace that tension type clamp?

Originally Posted by DieselFab67

It might be leaking from one of the transmission cooler lines. Sometimes just touching a rubber hose is enough to make them leak. Make sure you fix it though. Oil leaking there will attract dust and over time your intercooler, trans cooler, and radiator fins will start to plug with oily dirt.

[DieselFab67]

No... The constant pressure clamps work fine. The rubber of the lines may need to be replaced. Once they get set in a certain way, they like to leak if moved. Make sure that is where it's leaking first. Then try twisting the rubber lines back and forth a little. If it still leaks, probably a good idea to change them.

We have seen leaks on all kinds of rubber hoses where the "rubber takes a set" and if it isn't re-installed the exact same way, it leaks.