I have one of my cooler lines that corroded off at the nut where it attaches to the transmission. I can’t find new lines anywhere. I work at a parts store, and I can’t even find what kind of fitting it is called. It looks like a stub sticking out with a ring around it that an oring seals against. I was hoping they were a flare but no such luck…

 

What year is your truck? Your initial sentence about corroding at the nut implies a flare connection. But your mention of an o-ring sounds like a quick-connect. Some years had quick connects and some had flare. Post pics.

RockAuto carries replacement cooler lines - you might be able to get brands and part numbers to look up on 'son. One of mine rubbed through a while back and the replacement flare lines weren'tthe creates for fit and seal - I'm going with one of the hose kits

 

It’s a 93. It’s neither flared, nor a quick connect. I’ll get a picture later. I’ve been in the industry for 35 years and haven’t run across a fitting like this before.

 

Here’s a pic of the end that broke off right at the cooler. I’m guessing vibration and galvanic corrosion were to blame.

 

Looks a lot like the fitting you would find on the ends of a power steering pressure line.

 

It does. Where do I find one in northern Saskatchewan is the problem. They’re 1/2”. Haven’t found an application with a 1/2” ps line. I can’t believe the internet doesn’t have a solution to this that I can find. I’ve ordered a new cooler with npt ports. Unfortunately it won’t fit behind the grill as I have a 74 body on a 93 frame.

 

If there is a decent hydraulic shop in the area, pa/nip/lloyd, they should either have the fittings, or be able to access them. Most common for that fitting is gates, followed by weatherhead, then new line/green line. Most of them will be crimp fittings for hydraulic hose, but that works too, just have a line made up to your specs.