Transmission cooler line connection dilem | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

Transmission cooler line connection dilem

DFully

New Member
Joined
April 9, 2021
Messages
8
Reaction score
0
City, State
Willow Creek, California
Year, Model & Trim Level
2006 4.6L Eddie Bauer
I own a 2006 4.6L 3 Valve explorer with the 6R60 transmission, recently my radiator cracked along the top of the plastic causing a substantial leak. Now radiators are sold out ado the wait time is pretty good amount of time not having any wheels. I unfortunately could not wait the required time to stick with the Motorcraft radiator so instead I ordered the mishimoto OEM direct replacement with the lifetime warranty. I’ve used the warranty once already due to the shipping being so roughly handled the radiator was bent and leaked out before I even installed it so I waited another 3 weeks to get the replacement and after installing it everything was great ran good as new but after a few hundred miles I noticed a fairly small leak, I investigated further and I soon found out the leak was no longer a small one but a rather moderate and growing one. The leak I was able to diagnose as the transmission cooler line connector on the driver side was the culprit and after some research I found that the mishimoto radiators use the same cheap connectors as most of the non Motorcraft radiators use with only one o-ring located inside rather than two. My question is if I buy the dorman replacement will the thread size fit the mishimoto or how do I fix this dilemma? And to flush the intercooler what all is required since I’ll have to drain both coolant and the intercooler in order to properly install the dorman replacement?
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





Members have had issues with the Dorman radiator parts. I’d go somewhere that makes hydraulic hoses.or a transmission shop. They should be able to match up anything you need.
 






you can reuse your old trans line OEM fitting with new fresh orings.

since there is no any pipe crimp tools needed in GEN4 radiator side fittings and they all are threaded

motorcraft/ford parts sell this fittings and repair kits separated from the whole radiator assy..you just need to find the right one OEM fitting.
 






Okay but when you do get the right fittings how do I go about draining the intercooler so that coolant doesn’t get contaminated with transmission fluid or vice versa? Do I have to drain the coolant as well to swixb out the fitting f? My dad already took my original radiator to the dump so getting those fitting me off are no lnger an option but I definitely need the right one cause I can’t afford to lose anymore transmission fluid or coolant, my pocket book is taxed to the max and i don’t have another fro to the auto parts store in me again so thanks again all help is much appreciated
 






And you see your fluids contaminated right now?

Anyway

if it any chance for fluids to mix you will have to flush both engine and trans lines.
 






Tranny fluid in the coolant isn’t a huge deal. ANY coolant in the trans fluid is a death sentence for that transmission. They aren’t going to mix just swapping the radiator, or transmission cooler fittings.
 






Ditto, it's super rare for the ATF cooler inside the radiator to fail,mix fluids etc.

You have a new radiator, part of installing one is verifying that everything matches, that the line fittings are correct etc. You should always keep the old parts until you know the new ones and repair are done and successful. This is a learning experience, you probably won't throw away the old parts again without checking everything.

FYI, the normal ATF lines have an o-ring in the connection fitting, those are wear parts and usually need to be replaced. I wonder if all you need is a proper new o-ring. Are you sure that the fittings are different? They shouldn't be tightened together if they do not match, that can damage them.
 






Cheap Gen4 radiators equipped with the old design single O-rings seal threaded fitting (instead of the quality and OEM parts equipped with two trans line inlet O-rings)
 






Cheap Gen4 radiators equipped with the old design single O-rings seal threaded fitting (instead of the quality and OEM parts equipped with two trans line inlet O-rings)

Yes sure, but was the o-ring replaced? Those will almost always leak if they are left in there, or left out(they degrade over time). I have replaced all four pairs of those in my 2nd gen trucks, which use the old design. They work great, when they have a good proper o-ring in them. I discovered the need for the o-rings in older Fords myself.

I had an 86 Crown Vic P71 that I made trans lines for, to include a huge engine cooler for the trans. I did great to make them and not include any rubber hoses, just easy to come by steel fuel lines from the parts store. In the end, about half of the fittings leaked, those flare nut fittings aren't ideal for high pressure fluid. I thought of installing o-rings into the fittings, after tightening them a ton. The o-rings required very little torque on the fittings to keep them from leaking. They never leaked after that, although the used cooler did about nine years later.

I did that in about 1991, and I've done that many times since then, on all trans fittings that have the flared connection. That's old knowledge, and I wasn't the first to do it. The OEM's have learned it to over the years, and obviously they have upgraded more also. Fine, but prior fittings Ford used were terrible because they made them to flex in the connection, and those always developed leaks. The answer for those to was to change the fitting on the radiator, to the fixed style, and again use an o-ring in the fitting.
 






Tranny fluid in the coolant isn’t a huge deal. ANY coolant in the trans fluid is a death sentence for that transmission. They aren’t going to mix just swapping the radiator, or transmission cooler fittings.

I know this is an OLD thread but my subject matter/question is 100% relevant, so to ease future users in 'search' for finding answers, I'm continuing this conversation.

Regarding the comment above. I'm in the similar situation of needing to swap my radiator transmission-line connectors (2006 4.6L).

I've heard TWO firm opinions on this. One is that, by removing the fitting from the radiator, because a 'washer' or 'oring' (or something) inside the radiator, between the internal transmission cooler tank and and the radiator itself, can drop down, that there IS an opportunity for the coolant and transmission fluid to then mix. This is why I've (heard) that draining the coolant is 100% necessary. By re-installing the fitting (assuming you line everything up) and tightening, you re-create that internal seal in the radiator. The other is that, similar to the above, this *isn't* true and you CAN simply just swap out the connectors without any concern about a part "falling inside" the radiator etc.

I need to know which is true. I'm getting ready to swap my connectors to the better versions. If there IS a risk however of an internal washer/o-ring falling inside, etc, I'm going to just bypass the entire internal cooler and run through an external (which will be in addition to the stock external)


Thank you in advance for your help!!
 






I've never seen the suggested issue with some internal part or seal inside the radiator, the trans cooler holes, that could result in an internal leak. That has been suggested a couple of times on this forum, but it is likely to be a later model than the 2nd gen Explorers. I have seen many among 1980's and 1990's Fords, none with a possible issue inside the cooler fitting holes.

So you might research some more for the 2002 and newer Fords for such examples, or presume the suggestions of a problem, are unfounded. I would remove the trans fitting and have a close look at it, I would expect the internal cooler to be permanently mounted, without any internal built in sealing component. If there is something in there like that, I would be worried also.
 






Yeah I'm referring explicitly to gen4 2006-2010 explorers (the ones mentioned in this thread). Which is the generation I've seen this problem referred to in quite a few videos, but I've yet to find someone with a video of the problem "in action" (but HAVE seen a few members claim they've witnessed the issue themselves)

See 2nd comment from the bottom on this thread below. This is what I'm questioning. I hear/see it, but have never SEEN anyone show it. And plenty of others have claimed they've 'just swapped it out without issue'. So, which is true:


@Tech By Trade - Can you by chance comment on this? One question I have is, if only ONE of the fittings are removed, would the other side, still being tight, prevent the side you just removed from 'falling down'? And if it does fall down, how do you get it back up? (there's a joke there somewhere..)
 






Yeah I'm referring explicitly to gen4 2006-2010 explorers (the ones mentioned in this thread). Which is the generation I've seen this problem referred to in quite a few videos, but I've yet to find someone with a video of the problem "in action" (but HAVE seen a few members claim they've witnessed the issue themselves)

See 2nd comment from the bottom on this thread below. This is what I'm questioning. I hear/see it, but have never SEEN anyone show it. And plenty of others have claimed they've 'just swapped it out without issue'. So, which is true:


@Tech By Trade - Can you by chance comment on this? One question I have is, if only ONE of the fittings are removed, would the other side, still being tight, prevent the side you just removed from 'falling down'? And if it does fall down, how do you get it back up? (there's a joke there somewhere..)

Someone needs to post pictures of the offending radiators and those cooler fittings etc. I hope that simply removing the trans fitting from the radiator wouldn't create any problem, let the cooler fall down inside etc. Ford has done lots of dumb things over the decades, hopefully this isn't another example.
 






Yeah agreed 100%, but with so many comments about it, it has me worried.

Kinda leaning to just bypassing (since I have the 6r60 with an internal thermal valve, the idea of the radiator cooler 'helping the transmission warm up' doesn't really apply since fluid isn't running through that system when cold anyway, so really no downside in bypassing) - but - I DO prefer to keep things stock where possible, so would really like to just swap the connector, if it's a non-headache induced procedure LOL
 






I've never seen anything except for standard pipe thread fittings on radiator transmission cooler fittings on any vehicle. Some have o-rings, some don't. It's possible the fitting was overtightened and the plastic weld is breaking lose from the threaded slug on the radiator itself.

The cooler is part of the plastic end cap of the radiator, it's not a separate piece that can fall anywhere. They are just a fluid reservoir built into the plastic. Radiators are simple to replace. I've replaced lots of radiators on different vehicle makes and models. Never had a trans line leak.

I bypassed the cooler on my Explorer, but its mainly a trail rig and I wanted to separate the systems. I also rarely find myself in very cold environments. Cooler is kind of a misnomer, it's really there to rapidly warm the transmission fluid.
 






there is no such a internal seal inside, the only seal in the radiator its the cooler line fittings ones.
and no, as was mentioned above, the cooler cant fall or became loose .
 






Here is diagram of a common radiator. This is for a Lexus, but they are all basically the same. Some have more plastic top and bottom, but mostly the same as the picture.
A1_164080C_16400.png

The end caps are separate and crimped, glued, etc., to the sides of the cooling fins. There is nothing to leak into the coolant side as they are separate. That's why it's so rare to have one fail on the inside where it could mingle trans fluid and coolant. The only trans line leak I have ever seen at the radiator were due to bad o-rings or the threaded slug or bung breaking lose from the plastic due to overtightening. The bung usually has a head on it for a wrench to keep it stable while tightening the fittings.
 






Actually ive seen the old 3.0 4jx1 engine Isuzu Trooper ATF + coolant mixed because of the cracked a/t cooler tank
 






With all due respect, you guys are referencing 'your trucks' which are not 4th gen. I too have other vehicles with internal rad trans coolers (in fact, all my other vehicles do) - that do not have this potential problem, but that's not what I'm asking about. I'm looking for feedback from someone with direct experience with this exact model and radiator.
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





This video might give you some information. This YouTuber is extremely knowledgeable about Fords and he covers a lot of details when replacing the radiator. Some of them might answer your questions.

 






Back
Top