engine and Auto trans cooling question

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Dezerts10

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I am on the search to put a smaller radiator in my 4 runner so the radiator doesn't stick out below the frame rails so it is not something that is so easily taken out by a rock or something. I also want to do it so I can build a skid plate that isn't so vertical and ugly looking.



Question is I bought a 2.4 L radiator with trans cooler it is shorter and many people say it will work so I took the $126 plunge and bought a new Denso unit from Napa.



Next is to get it installed and run it for a few weeks before I take the 4runner out for new years weekend and play with it.



Question is I am thinking a small electric fan on the grille side of the radiator that pushed air through the radiator on a switch isn't a bad Idea
da3b95a3cf10699df175bc7ff77461e1.jpg
and also thinking about one of those extruded aluminum inline trans cooler mounted on the frame rail some where or even under the radiator might not be a bad idea.
8eba5e2ac5975c1f2e4641960d6fd49b.jpg




Thoughts? Anyone done this?
 
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i would get a more "conventional" remote trans cooler. but that's just me. and with a smaller rad, id be weary of putting a smaller single rad fan in there. but again, thats just me.
 
So you are swapping in a smaller radiator to avoid trail damage, but you want to mount a trans cooler on the frame rail for under the new radiator?

I'd put one in the standard spot behind the grill and call it a day.
 
Okay, first, and with all due respect, this is a terrible idea - why reduce your ability to cool your vehicle esp when offroading is a goal?

Second, that is what the front, lower engine cover's job is, to protect the radiator. If you think that isn't tough enough, aftermarket skids exist for this reason

Third, see below

aontkos said:
So you are swapping in a smaller radiator to avoid trail damage, but you want to mount a trans cooler on the frame rail for under the new radiator?

I'd put one in the standard spot behind the grill and call it a day.
Click to expand...

BFAD and millions more have done it http://www.toyota-4runner.org/3rd-g...oler-transmission-cooler-install-3rd-gen.html

Lastly, electric fans bring their own set of worries (I have run plenty of them) and the stock cooling system on the 4runner is pretty damn good. TBH I would consider an electric water pump (but don't) with an electric cooling fan for offroading, but leave it stock and save your money for busted trail parts.

No disrespect intended :lookout: good luck!
 
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Agree with everything Octane said. The stock cooling setup on these trucks is exceptionally powerful, as long as rads are changed every 100,000 miles and genuine Toyota coolant is used.

In all my years on this forum, I’ve heard of exactly zero damaged radiators as a result of trail damage. I would backburner this idea in favor of about 9,000 more applicable and beneficial mods.

Finally, I don’t recommend completely separating the trans and engine as the engine relies on the heat generated from the trans during each warm up cycle.
 
OP wants to improve the looks on the bottom front of the 4r by shortening the rad to not go beyond the bottom frame rail, and in turn run a more horizontal skid that doesn't have to protect the protrusion of the stock radiator below the frame rail. it can be done but, it sounds waste of money just to improve the looks.
You'll have to find a way to add more cooling (electric fans) cause your taking cooling away with a smaller radiator. And you'll have to fab up a custom skid without the fron vert in it.
Simpler is better and the stock setup has proven itself time and time again to be more than adiquate to do the job. I would save that mod money for more worth while mods and less headaches.
 
tarsun said:
i would get a more "conventional" remote trans cooler. but that's just me. and with a smaller rad, id be weary of putting a smaller single rad fan in there. but again, thats just me.
Click to expand...

If I put a fan in front of the radiator I will find one single minimum 12" fan that covers the radiator.

aontkos said:
So you are swapping in a smaller radiator to avoid trail damage, but you want to mount a trans cooler on the frame rail for under the new radiator?

I'd put one in the standard spot behind the grill and call it a day.
Click to expand...

the inline cooler would be just for more cooling and be mounted on the inside of the frame rail or protected by the skid plate some where.

absalom said:
Agree with everything Octane said. The stock cooling setup on these trucks is exceptionally powerful, as long as rads are changed every 100,000 miles and genuine Toyota coolant is used.

In all my years on this forum, I’ve heard of exactly zero damaged radiators as a result of trail damage. I would backburner this idea in favor of about 9,000 more applicable and beneficial mods.

Finally, I don’t recommend completely separating the trans and engine as the engine relies on the heat generated from the trans during each warm up cycle.
Click to expand...

the radiator I bought to see if it works has a built in cooler as well. the inline would just be fore extra cooling similar to a power steering system inline cooler.

Im going to swap in the radiator I bought from napa and see what happens this weekend. If I can get the rest of the suspension completed ill drive the truck for at least a week to work to see how the cooling system acts. Then new years weekend will be the real test for off road use and driving.
 
Radiator for a 3.4 5speed...and BM supercooler 7064 mounted between rad and condenser...
Solves lower clearance problems and no reduction in cooling capacity...
My $0.02


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Devo9000 said:
Radiator for a 3.4 5speed...and BM supercooler 7064 mounted between rad and condenser...
Solves lower clearance problems and no reduction in cooling capacity...
My $0.02


Sent from my iPhone using Tapatalk
Click to expand...
Toyota designed the radiator and transmission cooler to share a common wall or membrane for a reason. Separating the two negatively impacts the warm-up performance of both systems unnecessarily. Keep in mind, much of the associated wear and tear to an engine happens during the warm-up period, so it's highly desirable to have it up to operating temperature ASAP.

Can anyone in this thread find one example of a trail-damaged radiator? It just seems like a tremendous amount of time, money, and labor for what most would rightly consider to be a non-issue.
 
absalom said:
Toyota designed the radiator and transmission cooler to share a common wall or membrane for a reason. Separating the two negatively impacts the warm-up performance of both systems unnecessarily. Keep in mind, much of the associated wear and tear to an engine happens during the warm-up period, so it's highly desirable to have it up to operating temperature ASAP.

Can anyone in this thread find one example of a trail-damaged radiator? It just seems like a tremendous amount of time, money, and labor for what most would rightly consider to be a non-issue.
Click to expand...

The majority of wear occurring to an engine on startup is due to lack of oil pressure and lack of oil for the first few seconds after start up. Not really due to the actual temp of the engine/coolant.

To the OP, 2.4 or 2.7L radiator should work fine. Obviously it would behoove you to drive the truck hard while monitoring coolant temps with an actual gauge and not just the stock gauge while you are figuring out if it will work. I'd also run the largest trans cooler you can fit with a similar design to the B&M one posted earlier. High trans temps kill transmissions, not slow fluid warm up times. Make sure you show us your bumper design after all is said and done.
 
[MENTION=149702]Dezerts10[/MENTION]

I wheel pretty hard when I can and there is a skid plate protecting my stock radiator. I have never damaged the rad but I do have to re-paint the skid often. I also run an inl-line trans cooler with a 7" electric fan. Off road on steep pulls I've never seen the trans temps get over 195 with this combo. If I remember to turn the fan on first I've never seen them over 185. My engine runs between 195-200. Once torque pro went up to 201.6 but that was in really high ambient temps. This is just my set-up but it keeps everything really cool.

Go ahead with your plan. I think it will work fine for city/highway driving. I would take a really hard look at what your trans and engine temps get up to wheeling though. I'm guessing your engine temps will be fairly normal. I'm also guessing that your going to see really high trans temps. The idiot light comes on at 280 or so IIRC. Mine came on twice before I added the in-line cooler and fan. It's never come close to coming on since.

Let us know what your temps get to, I'm really curious to know.
 
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I have the scan gauge 2 I’ll use for monitoring the temps. I’m slightly concerned but not enough to really worry at this point unless the city driving I’ll do before taking it out New Years weekend happens and the temps are high.

I know heat kills transmissions and engines and cooling problems are the only thing u ever worry about when I start screwing with stuff.

Only one way to find out if it will work or not and it only going to cost some time and about $150.

The radiator bolts in and I’m not doing any permanent fabrication on a bumper or core support changed until I’m 100% confident in the smaller radiator / trans cooler working.

I’ll be sure to have a cooler with me no matter what though.


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Haven’t gotten to drive it yet but here’s a before with the stock 3.4l radiator
c0fe8e0918bc6d5f603af9fd378046bc.jpg


And after with a 2000 2.4l automatic radiator
405da6dfbed6f55f773f19ef62376ab4.jpg


It took all the coolant but maybe a quart that the 3.4l radiator did and I ran it and let it idle for a good 20 mind so far and watched the gauge and only saw 181 degrees and that was after using the gas pedal to get it to about 3k rpm for a minute.

I saved the stock stuff and will take it on the New Years trip just in case and I plan to see if a 3.4l shroud will fit before I do anything else. I haven’t had a radiator shroud since I become the owner of it


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how many cores does the replacement radiator have? The stock radiator has two cores, iirc. another option, though late, would be to use a three-core radiator to increase cooling efficiency. The stock shroud should still fit with a three-core radiator.
 
HiluxSurf SSR-G said:
how many cores does the replacement radiator have? The stock radiator has two cores, iirc. another option, though late, would be to use a three-core radiator to increase cooling efficiency. The stock shroud should still fit with a three-core radiator.
Click to expand...



I don’t know how to tell how many fire honestly *♂️


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the number of cores is the number of rows of vertical tubes in the radiator in the transverse direction (i.e., from the bumper side to the engine side).
 
Well drove around this weekend towing a trailer and in the dezert for well over 400 miles and never saw a temp above 193 when towing up a grade. Never saw above 188 even in sand washes

Let it idle for like 20 mins and saw 202 on the scan gauge.

Not sure if these numbers are normal but I was semi happy. I don’t like seeing a digital number persay and the factory gauge stayed in the middle.

I need to put a dan shroud on it and I think it would cool
Even better so that’s in plan.


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