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AOD Transmission cooler lines

Gas Pig

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I’m in the process of doing a build with an AOD and I’m figuring out the trans lines to the radiator. I’m thinking of not doing metal lines because I’m not sure they even sell lines for this application.

Anyways I’m thinking hose of some kind. But I have read that simple rubber hose is not desirable for a few reasons but AN PTFE is a good choice, or is that overkill? Also there is a host of different types PTFE fittings which I have know idea where to start.

Any thoughts would be a huge help, thanks!
 

bax

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Look at Earl's super stock hose. It's blue. I use the push on Aluminum AN fittings with it. No clamps needed. it looks good when finished.
 

bax

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Look at Earl's super stock hose. It's blue. I use the push on Aluminum AN fittings with it. No clamps needed. it looks good when finished.
It is also in black. I like it.
 

toddz69

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PTFE hose would be fine for transmission cooling lines - I may switch mine at some point for that too. I currently use the cloth-covered high-pressure hose that a lot of use for p/s and hydroboost lines for mine.

Todd Z.
 

bcmbcmbcm

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I went through this recently too. Its worth the $ to swap out your cooler (if you already have one) with one that already has AN fittings on it.
 
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Gas Pig

Gas Pig

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Ok I’m horrible at plumbing stuff! lol

Anyways it looks like the AOD in and out ports are for 3/8 flared metal lines. Should I pull those fittings or look for an adapter to AN fitting?

On aluminum aftermarket radiator it looking to a 1/4 npt?

So what are my options?
 

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bax

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That should be a pipe thread coming out of both the trans and the radiator. real easy to go from pipe to AN
 

ba123

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I'm about to do mine with Nicop 3/8 line

The fittings in the trans are 1/4" NPSM (not NPT, they are straight, not tapered) and you can find a million adapters to AN or there are some 1/2-20 adapters I found as well that was going to use but not.

The fittings on my Howe radiator are 1/4 NPT (which you can find AN adapters for as well..)
 
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ba123

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If you search "Transmission line fittings AOD" on Summit, you'll find what you're looking for for the AOD side, like this:


And if you search 1/4" NPT to -6an you'll find lots for that (assuming that's what your radiator is, make sure first:)

 

Oldtimer

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So does Gas Pig remove and replace these (bead blasted) fittings with the AN adapters?

2023-05-03_095400.jpg
 

ba123

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Those are most likely for stock hard 5/16 lines. If going AN, you'd need to remove those and put a 1/4" NPSM to -6AN transmission fitting like the one I linked above yes, instead of those fittings. They just unscrew, might have loctite and be tough to remove but they do unscrew, normal right hand thread.

Also, the Upper line is the HOT line OUT and the bottom line is the COOL line back in. (And I think in the next version, AODE, that was flipped).
 
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Gas Pig

Gas Pig

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I'm about to do mine with Nicop 3/8 line

The fittings in the trans are 1/4" NPSM (not NPT, they are straight, not tapered) and you can find a million adapters to AN or there are some 1/2-20 adapters I found as well that was going to use but not.

The fittings on my Howe radiator are 1/4 NPT (which you can find AN adapters for as well..)
So I pulled the two fittings out of the trans and as expected they are straight thread. They measured 1/2” so it’s safe to say the are 1/2-20?
 

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ba123

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So I pulled the two fittings out of the trans and as expected they are straight thread. They measured 1/2” so it’s safe to say the are 1/2-20?
NO, and that is the most annoying thing ever. I even got into an argument the other day at Ace with the guy who was supposed to know what he was doing and said it must be right cause he can make 1 full turn in the threads…. Anyway, 1/4” NPSM is actually slightly larger than 1/2” actual.

I’m no expert at thread identification, I like to thread things in to be sure, I don’t like cross threading or fixing threads and if I do fix them, it was likely messed up by someone else. I also like being sure of what I’m doing and I searched everywhere I could to be absolutely sure that these threads are 1/4” NPSM, if you indeed have a Ford AOD transmission. Although, I’m pretty sure the AODE had the same threads and only change was that the in and out are reversed. If fact, I’m pretty sure there are more trannys that are 1/4 npsm than any other thread. If all you do is go on Summit.com and search “transmission line adapter” I’m pretty sure that is what will come up the most.

And also, you might actually get a 1/2-20 partially threaded, but don’t do it, it is close. 1/4-18 is NPSM and it’s not that different.
 

ba123

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Just found this…check it out:
https://www.restek.com/en/chromablo...18-national-pipe-thread-tapered-npt-fittings/

I know it’s for not, but the only difference is npt is tapered.

Another good one:
https://www.freshwatersystems.com/blogs/blog/how-to-determine-pipe-thread-type-and-pipe

Here’s a good read and what I got into the argument at Ace about…he tried to tell me that MIP is Male and FIP is female and while that is generally true, an MIP and FIP fitting is not made to fit together.
https://www.pvcworkshop.com/mip-vs-fip/
 
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Oldtimer

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1/4” NPSM: 18 threads per inch, OD measures .517"-.526"

Note that straight pipe threads, unlike tapered pipe thread do not provide any sealing function. Typically, a design that utilizes a straight pipe thread will incorporate a sealing features, like an oring to facilitate fluid sealing.
2023-05-04_130752.jpg
 
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Gas Pig

Gas Pig

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1/4” NPSM: 18 threads per inch, OD measures .517"-.526"

Note that straight pipe threads, unlike tapered pipe thread do not provide any sealing function. Typically, a design that utilizes a straight pipe thread will incorporate a sealing features, like an oring to facilitate fluid sealing.
View attachment 902101
Yes I found something just like on Amazon but it has copper crush seal instead of the nylon.
 
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Gas Pig

Gas Pig

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I think I have the adapters figured out. What the actual AN fitting and themselves. There seems to be several types. Personally I’m most familiar with the push on two barbed fittings. But there are then kind that have inserts with outer twist locking nut.

Also I have noticed there is a bunch of different type PTFE hose, some of which is ver expensive. I’m not what is actually necessary.

Thanks to all for your guys’ input and help!
 

ba123

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I've never seen one with copper but that doesn't mean it isn't good. I'm not even sure about a washer or not, not to contradict @Oldtimer , but there isn't one on the stock fitting and the fitting I had on there first didn't go all the way for a washer to even make contact.

I would use this: https://www.permatex.com/products/t...nts/permatex-seal-lock-thread-compound-35-ml/

but just on that fitting, not the AN fittings. That stuff ROCKS! (and safe for so many fluid types). It's thread sealant and blue threadlocker in one.

Also, I wouldn't cross an fitting brands unless you have no choice. Same with hose. Use one mf's hose and fittings. Some very knowledgeable people here that have done a ton with fittings like @jamesroney will tell you that some aren't even really AN and are JIC which looks the same, has the same 37° angle but the threads are slightly different. If you use all the same manufacturer, that shouldn't matter.

As far as deciding which one to go with, put together a list of fittings you need and see which company makes them all and is in your budget.. Some seem to have inexpensive hose, a few inexpensive fittings, but then ream you on others to make up for all of it and then some. Some have all reasonable fitting prices but more expensive hose. Also make sure the hose is good for Transmission Fluid, which I think has to be PTFE hose. But again, all hoses are different. Don't pick a Russell Hose and then Summit fittings. The fittings have to be right for the hose.
 

jamesroney

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I think I have the adapters figured out. What the actual AN fitting and themselves. There seems to be several types. Personally I’m most familiar with the push on two barbed fittings. But there are then kind that have inserts with outer twist locking nut.

Also I have noticed there is a bunch of different type PTFE hose, some of which is ver expensive. I’m not what is actually necessary.

Thanks to all for your guys’ input and help!
Keep in mind that the Earls Super Stock hose is not recommended for use on Automatic Transmissions at temperatures above 250F. It has excellent chemical resistance to ATF, but it can't handle high heat.

The vast majority of users in the NRHA only run their transmissions for about 15 seconds. So it's just fine for that. But if you tow, or haul, or cook your ATF...that hose is not good.

PS hose, and Automatic Transmission Cooler hose should meet SAE-J2076 and get you to 300F.

The "very expensive" PTFE hose is good for 400 degrees F, and 3,000 PSI. I don't like it for hydraulic pressure hose, because it tends to abraid against itself inside the jacket...and if you let it move around and rub against metal...it will fail internally.

None of that push on hose actually meets the AN spec. The vendors just cleverly use -AN to designate a SIZE. Not to designate the SPEC. So the Parker push lok -6AN hose is only -6AN SIZE...which is something like .320 inside diameter if its PTFE.

Oh, and thanks for the shout out... @ba123 I've been lurking, but I read that post from pvcworkshop about FIP and MIP, and I had to turn off my computer...It made my head hurt.
 
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