When I changed out my auto trans, I found the quick disconnect fittings that retain the cooler lines into the trans contained a little plastic clip, that had become brittle, and broke when I took them out.
If this happens to you, I found a solution
3/8" Fuel Injection filter quick disconnects are almost identical, and do in fact work
In this pic, you can see the original metal fitting, which retains the 3/8" cooler pipe, with 2 o-rings and the plastic clip
(the pic shows 5 o-rings, the original green one, 2 x Imperial, and 2 x metric)
So I fitted the new clip (pictured) with 2 new o-rings and it holds together as it should. It is very important to remove and clean any old pieces of plastic, dirt, or o-ring from the fitting
The whole fitting is available as a Dorman product from USA
If I had an insurmountable issue, I would attempt to replace the M14 x 1.5 quick disconnect with this
https://www.ebay.com.au/itm/Racework...72.m2749.l2648
(its a m14 x 1.5 male with 3/8 barbed fitting, so you can just run rubber lines all the way, as the quick disconnects at the other end will probably be either shot, or leaking...you can also get fancy with other types of quick disconnects
I ordered one anyway, as I can use it to measure trans pressure, if ever needed.
The T55 has the same thread,
I also ordered an M14 x 1.5 to 1/8 NPT adaptor so I can fit a trans temp gauge