FJ62 Transmission Oil cooler install (1 Viewer)

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I believe there is some merit in the concept of heating the fluid....especially in cold climate in the winter..like Canada and other locations. Generally you are concerned about the fluid getting too hot, but I would assume that dealing with severe cold for extended periods might not be so good either.

That's what I go off of. I figure if it goes through the aux cooler first, it will then go through the heat exchanger (in the radiator) which, in cold weather, will heat the fluid to a good operating temp (180-200* F). In hot weather, depending on how much heat the fluid loses in the aux cooler, the heat exchanger will either warm it back up slightly, or further cool it to get down to the safe operating temp.

Where I live we can get winters in sub zero temps and summers in triple digits, so I think having the fluid go from the tranny through the aux cooler and then through the radiator is the best bet.
 
The ideal flow:

1. TMS
2. Heat exchanger inside radiator
3. Air cooled fin cooler mounted in front of radiator.
4. Back to TMS
 
The ideal flow:

1. TMS
2. Heat exchanger inside radiator
3. Air cooled fin cooler mounted in front of radiator.
4. Back to TMS

So if I follow this flow:
1 & 2 - No change to current lines
3. Route "out" line from radiator to AUX cooler
4. Aux cooler "out" to TMS

Which of the two lines that run from the TMS to the Radiator and back is the "out/return" line that I need to route through the AUX cooler? I looked through the FSM and didn't see anything.
 
Those are general flow guidelines. Since I don't have a 62, I can't say definitively which side of the rad is the return line, but logic dictates that the passenger's side is the return line, as that is the coolest spot on the radiator. Maybe someone with a 62 can verify.
 
Cooler-Flow.jpg
 
For warmer climates that would make the most sense, but I can't imagine having overly cooled fluid going into the transmission being good when you're down into single digit and below temps.

OTOH, I know Rodney follows the same idea as the pic you posted. I wonder what his take on cold weather use would be.
 
For warmer climates that would make the most sense, but I can't imagine having overly cooled fluid going into the transmission being good when you're down into single digit and below temps.

OTOH, I know Rodney follows the same idea as the pic you posted. I wonder what his take on cold weather use would be.


The picture is exactly how I described it....and how it should be done...nothing unique to a land cruiser about this. My 3/4 ton GM pickup has an aux trans cooler from OEM...plumbed exactly this way...every truck I've owned with aux cooler same thing.

Again the fluid is not overly cooled in the winter....if you wanted it overly cooled in the winter you would take the radiator out of the equation.
 
That's what I go off of. I figure if it goes through the aux cooler first, it will then go through the heat exchanger (in the radiator) which, in cold weather, will heat the fluid to a good operating temp (180-200* F). In hot weather, depending on how much heat the fluid loses in the aux cooler, the heat exchanger will either warm it back up slightly, or further cool it to get down to the safe operating temp.

Where I live we can get winters in sub zero temps and summers in triple digits, so I think having the fluid go from the tranny through the aux cooler and then through the radiator is the best bet.


not a good idea.... I've not see anyone advocate for that...:"from aux cooler back to radiator then to transmission".... I've never seen that...even on Canada spec big trucks with aux coolers. The pic I posted below or above is pretty much the industry standard...across all the OEM's I've seen...even in the big trucks....class 8. I think some vehicles may have a thermostat built into the cooler lines. I do agree the cold can be an issue but I don't' think the answer is to deviate from the noted routing of the fluid.
 
not a good idea.... I've not see anyone advocate for that...:"from aux cooler back to radiator then to transmission".... I've never seen that...even on Canada spec big trucks with aux coolers. The pic I posted below or above is pretty much the industry standard...across all the OEM's I've seen...even in the big trucks....class 8. I think some vehicles may have a thermostat built into the cooler lines. I do agree the cold can be an issue but I don't' think the answer is to deviate from the noted routing of the fluid.
I had gotten it from another Mudder (I forget who) who did his that way (the way I described) and when he explained it, it made sense to me.

Honestly I'm probably just overthinking it like I have a bad habit of doing.
 
Rodney has always espoused that the cooler the ATF the better. Room temp is good, in his words. Then again, he's from the hottest part of OZ where they are all mad as cut snakes. That's an Aussie expression so don't ask me. I've run the standard setup of from the passenger side of the OEM radiator outlet to the auxiliary cooler input and from there to the transmission input. Bottom line the cooler the ATF the better. Living in Colorado and driving and wheeling year 'round at treeline and higher at temps well below 0*, the Rodney Extreme transmission in nearly ten years hasn't skipped a beat. If my truck's original A440F had enjoyed an outboard cooler it might just still be alive today but since it didn't, keeping the fluid as cool as possible has always made sense to me. Running from the aux cooler to the factory radiator goes against that logic no matter what latitude your truck operates in.
 
it might be one thing if you were exposed to a certain narrow range of temps such that you might tailor the install to suit that climate....but for those of us in North America I think the OEM's have it figured out, so its a smart move in my view to replicate their setups.
 
Rodney has always espoused that the cooler the ATF the better. Room temp is good, in his words. Then again, he's from the hottest part of OZ where they are all mad as cut snakes. That's an Aussie expression so don't ask me. I've run the standard setup of from the passenger side of the OEM radiator outlet to the auxiliary cooler input and from there to the transmission input. Bottom line the cooler the ATF the better. Living in Colorado and driving and wheeling year 'round at treeline and higher at temps well below 0*, the Rodney Extreme transmission in nearly ten years hasn't skipped a beat. If my truck's original A440F had enjoyed an outboard cooler it might just still be alive today but since it didn't, keeping the fluid as cool as possible has always made sense to me. Running from the aux cooler to the factory radiator goes against that logic no matter what latitude your truck operates in.
I had forgotten you're using one of his transmissions along with a cooler. If you don't have any issues in winter temps with your rig, then I'd say I'll go with the illustration Elbert posted.

Evidence over theory is all I need.
 

Rodney has always espoused that the cooler the ATF the better. Room temp is good, in his words. Then again, he's from the hottest part of OZ where they are all mad as cut snakes. That's an Aussie expression so don't ask me. I've run the standard setup of from the passenger side of the OEM radiator outlet to the auxiliary cooler input and from there to the transmission input. Bottom line the cooler the ATF the better. Living in Colorado and driving and wheeling year 'round at treeline and higher at temps well below 0*, the Rodney Extreme transmission in nearly ten years hasn't skipped a beat. If my truck's original A440F had enjoyed an outboard cooler it might just still be alive today but since it didn't, keeping the fluid as cool as possible has always made sense to me. Running from the aux cooler to the factory radiator goes against that logic no matter what latitude your truck operates in.

The diagram and part in bold is kind of what I was looking for. I appreciate everyone's input to this thread; think I'm going to tackle this on Saturday.
 
14x1.5 in the tranny and rad. I used 6an hose and fittings as well. Worked great.
 
This exact question was just asked and the thread is still on the front page
 
Install was smooth except for unscrewing some of the ancient hose to metal pipe connections, first time working with A/N connectors/hose, easy once you do the first one, a little oil on the connector that drives into the hose end makes it much easier. IMG_20170714_161118878.jpg. Thanks for the great thread! I used XRP A/N fittings and Earl's metric-AN adaptor, and high-temp thread sealer on the NPT fitting on the cooler, removed all the old metal pipes/flexible hose and ran the lines directly from the transmission to the cooler and back.
 

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