any idea what size the fittings are that bolt to the side of the transmission? i'm gonna replace the steel lines with some -6 AN stuff. the steel lines ALWAYS break and are hard to work with. anyhow, i was just wondering if anyone knew what the fittings where. save me some time from taking a fitting off a broke trans and running it to lowes to figure out pipe thread style. (i believe it to be NPT of some sort, probably 1/2" or 3/4")

It's the same fitting that comes on 5/16 brake line. Definitely not NPT - the threads aren't tapered. I believe they are called inverted 45° flare fittings.
Just reread yours, the fittings that actually thread into the tranny are pipe thread, but I don't know what size.

The lines themselves are 5/16" I.F., threaded into adapters that go into some sort of NPT in the case itself.

Right; I think they're ¼" pipe. That size is about ½" OD.

yeah, i'm gonna replace the whole fitting, the one that actually threads into the tranny. i don't care what size the lines are, lol!

I have never had a problem with mine. It is about 6 diffrent pieces, with compression fittings. I have short pieces near the transmission so i can undo the compression fitting that are easy to get to and take the transmission out without having to fight with a wrench to get the lines out of the transmission.

hey matt, when did transmissions get coolant? You mean trans cooler lines.

well that nice. i'd like something that looks a little more professional. i got some extra cash coming my way from my tax return, and this is one thing i'd like to do. i'm not going all out with stainless braded lines for the cooler lines, but i am going to use the twist lock hose. so it's pratical, i promise. i've had trans/motors in and out of the car so much in the past and i like making things easier to work on. when it's easy to work on, i have more fun with it. make sense?

so, anyone know the size to the adapter fittings for the cooler lines for a th350

If you take the adapters already on the transmission off then the thread are -6 x 1/4NPS. The cheapest I have found is at http://cgi.ebay.com/ebaymotors/6-AN-...mZ270346877435

If you leave that adapter on the transmission then the part you need for the radiator and transmission should be the same, which is -6 x 1/2-20 inverted flare http://store.summitracing.com/partde...0&autoview=sku

using anything but steel lines is a gamble. the exhaust is right there. Trans fluid is very flammable. connections tend to leak, not recommending anything but steel at the trans connections. I have caught many cars on fire just filling them up when they burp after a overhaul, and that isn't even at driving temps since the hood is open. I'm not fire prone but did burn a whole car to the ground when a pressure gauge line (flexible) ruptured. All I could do was watch it burn. Just some thoughts on how to use your tax return responsibly. ha.

I was just about to hook up some new cooler lines and now I gotta go buy some new line cause you freaked me out! I am going to compromise though with steel braided.

with adapetrs in the case they are 3/8npt, with out adapters they are 5/16 npt i belive.