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Barbed fittings for transmission cooler lines?

Nice mike! I have some leftover firesleeve for the lines by the exhaust if you can use it:). ATF is pretty flammable, I seem to remember that most of the trucks that have burnt to the ground in the dez are from atf leaks:).

this thread makes me all kinds of happy. Gonna have to get those fittings next time I work on the tranny lines... I hate quickdisconnects with a passion.

If you can find a 9/16-17 threaded pipe fitting anywhere, it is really really damn close to m14x1.5. Note that I don't think such a thing exists, I just ran the calculations to convert to SAE :dunce:

Do not use tapered pipe threads for this, the case is cast aluminum and will crack:).
 
Lots of questions, lol. Lets see if I can answer them all...

Just clarifying, with the 90 fittings, if it is stated to be for -6 AN hose, than it can either be used with the -6 AN hose, or just high pressure 3/8 hose?
I'm using high pressure oil resistant power steering/transmission cooler hose. With the -6 barbed fitting you can use any hose with a 3/8ths ID. The guy at Earls told me you don't need to run a clamp with these fittings but I'm throwing one on there anyway.

Yeah, I've heard that about those fittings too - not needing a hose clamp. Never been brave enough to run without the clamp though!

Nice mike! I have some leftover firesleeve for the lines by the exhaust if you can use it:). ATF is pretty flammable, I seem to remember that most of the trucks that have burnt to the ground in the dez are from atf leaks:).
Do not use tapered pipe threads for this, the case is cast aluminum and will crack:).

We can attest to the ATF being flammable. And it doesn't take much to set it off. And the big pool on the ground under the car will be burning too.
 
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Yeah... I am not sure I would have the balls to run a fitting without a clamp, even if it said it was OK :shocked:

As for burning ATF, I know of a couple rigs that have gone up in smoke due to it. I know it burns real nice in a military multifuel engine, too.
 
it took me a while to dig this info up, so I'm adding it to the thread for future reference.


the forward connection on the transmission is the output, and should run to the lowest point on your cooler, and the rear most port is the return line. the reason for running it this way is so the transmission is pushing the fluid against gravity to move it through the cooler, instead of reaching the highest point and starting a siphon effect and draining back to the trans before it's cooled properly. It will likely only make a small difference in cooling, but this way will make the cooler perform the most efficiently.

:cheers:
 
yes 3/8s steel hard line. I'm flaring the ends and double clamping the hose onto the line.

have you considered using these things? http://www.youtube.com/watch?v=r02AKbp2WMY&feature=player_embedded

also, how you going from outside the cab, into the cab? hole and grommet? im considering adding a flat peice of steel, and running steel bulkhead fittings to get in cab.

anyone have any opinions on -8 lines instead of -6? would the pressure drop be too much? what about adding inline oil filters?
 
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I am a poor SOB and made my own adapters

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I'm looking to put barbed fittings into the transmission so I can run hose directly off of the trans without using the quick disconnects, anyone know of a part number? I've been searching for the last hour and all I can find is threads on cutting the stock lines with a tube cutter and attaching the hose there. That is NOT what I want to do. I want to replace the fittings in the transmission.

I'm not opposed to using adapters and such to get to the barb, but I'm having trouble finding a fitting other than a quick disconnect that would screw into the 14x1.5mm o-ring sealed hole in the trans. adapters would work well anyway because then I could put 90° fittings on it and run the lines towards the back where my cooler and fan are.

95 aw4 if that matters.
:helpme:

I got tired of those QD fittings as well (about the third time I replaced the O-rings for no good reason...)

My solution?

- Go get cooler fittings from Toyota for the Supra (more meat to work with.)
- Go get 3/8"NPT to -6AN adapter fittings from any fluid power house (or Earl's, or Russell, ...)
- Cut the ends of the Toyota fittings to present a flush surface and dress (cosmetic step, mainly.)
- Drill and tap to accept 3/8" NPT.
- Install the adapter fittings (I used LocTite #545 Hydraulic Sealer for the threads, but LocTite PST or even PTFE pipe dope will work. Pressure is residual.)
- Replace the OEM fittings with the Toyota fittings. (If you like, you can send the OEM fittings to me so I can modify them to go into the Parts Exchange. It's a bit more work on the Jeep fittings than the Toyota fittings.)

While you were getting your 3/8"NPT to -6 fittings, you should have picked up some low-pressure hydraulic hose (working pressure 50-100psig is overkill) and barbed fittings to match. You can get hose and fittings that won't require clamps - although you can still use them for "insurance" if you like. The fittings are reusable, just slit the hose to remove and replace. Buy the hose in bulk so you have plenty for later. A 3/8" ID hose will be easy to find barbed -6AN fittings for, and will also fit your transmission cooler (which should also accept a 3/8" ID hose. Clamp here.)

Except for the Toyota fittings, I know you can pick up everything off-the-shelf at the local Parker-Hannifin Fluid Power dealer without any trouble. After all, that's where I got my stuff.

NOTES:
- Pressure, as mentioned, is "residual" (it's mainly enough to keep the fluid flowing. The work has already been done by the time the fluid gets to the cooler.) I had a line pop on a cooler once on my 87 - I got drenched, but it was otherwise a good deal less offensive than a garden hose from two feet away.

- Unless you're going to upsize everything, there's no reason to go larger than 3/8" ID hose. The cooler itself is sized for a 3/8" hose (and runs 5/16"-3/8" tube ID,) and the ports & fittings in the transmission would have to be drilled out for 1/2" ID hose to make sense. No point in going any larger.

- Don't drill out the ports in the side of the transmission case to rethread - aluminum isn't very strong, and there isn't much meat there. Use the OEM fittings to make adapters (Jeep or Toyota) instead, it will be more reliable. Don't forget to replace the O-ring on the fitting proper (I don't recall the size, but I didn't have any trouble finding them locally. Buna-N or Viton are the preferred materials here, so go to a parts house or a fluid power shop instead of the hardware store. ATF will eat up hardware store O-rings without much effort...)

- The "reusable" "no-clamp" fittings should only be used with the hose they're designed for. Clamps should be used with any other hose. Period. The "no-clamp" fittings, however, will work with the hose they're designed for for an indefinite time, provided the working pressure is not exceeded. NB: Max pressure inside a properly-working AW4 is somewhere around 300psig - and I've seen hose and reusable fittings up to 500psig. The hose and fittings I used for my cooler setup were rated for 50psig, and ran just fine for years. No, I didn't use clamps on the fittings.

- If you want to go through sheetmetal anywhere, use a bulkhead fitting! It's kinda like using a pass-through post for a high-current electrical lead - sure, you could run the wire straight through, but how long will you get away with it? Do it right and forget about it.
 
have you considered using these things? http://www.youtube.com/watch?v=r02AKbp2WMY&feature=player_embedded

also, how you going from outside the cab, into the cab? hole and grommet? im considering adding a flat peice of steel, and running steel bulkhead fittings to get in cab.

anyone have any opinions on -8 lines instead of -6? would the pressure drop be too much? what about adding inline oil filters?

come take a look sometime this week if you have time. I went in under the rear seat and along the floor.
 
I was just wondering if anyone did it like the article that was posted and if you did; did you have any pictures.

I was looking at doing something like this but without the huge cooler and the in line filter.


Also does anyone have any part numbers for the block off's for the radiator? Pics?

Thanks,
Lindsey
 
you don't need to block off the cooler in the radiator, once you remove the lines it will drain and that's it.
 
not sure, but i can tell you my cooler sells for 80 bucks, the guage is around 50, and 50 in fittings. plus another 30 for hose and 20-30 for the hard lines i ran down the underside of the body. So I'm into it about 250 or so
 
yeah, the only reason to block the ports on the radiator is to keep crap from collecting in there and maybe causing corrosion. A few corks or rubber plugs or some RTV will do fine.
 
got $200 in my cooler/fan/sending unit. probably another $150 in fittings/bling before im done.... great thing about this thread, is grimm is doing it for a lot cheaper, you can scale it to how much coin you want to spend.

i got my cooler today, but on saturday i went out to the jeep to find leaking cooler softlines! PSHUGH!! those lines were coming off, sooner then expected! so i made up a 10" -6 line, with 2 90 ends to temp bypass the cooler untill i can get it setup completely... im going to throw that bypass hose in the spare parts bag, as it would be quite handy if someone was having issues away from home!
 
Old Thread but I did the fitting replacement last week and got rid of all the hard lines. Boy is it nice to not have trans fluid all over the driveway!

The fittings are expensive but $50 to make it work and stop leaking is worth it, I also have more clearance from the exhaust now 6+ inches as opposed to before the hard lines could touch it.
 
Safety & reliability were my two main concerns. With the quick disconnects if you break the plastic piece that holds it together or the o-ring fails inside the fitting you have ATF under pressure leaking dangerously close to the exhaust pipe, and no way to repair it on the trail or the side of the road. With these, if a hose should fail you can replace it and keep going.

Glad it worked out for you :cheers:
 
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