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Overkill or a problem waiting to happen?

jeffncs

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May 4, 2004
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94 5.0 with serpentine setup; using an Amazon’s finest radiator from a a/c equipped 94 explorer.

I don’t trust the radiator to not crack and destroy my rebuilt c4 so I opted to use a pair of trans coolers in series. Installed in front of the radiator, does anyone see any issues?

Truck will be driven all year in NC (hot summers) and see time on the mud and rocks.

Note - the return line was a hair short so I’m waiting on a splice fitting to finish the loop

IMG_0562.jpeg
 

904Bronco

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I see more points of failures with the two coolers and lines... But I will state that I am not a transmission specialist, I don't know if this is over kill or just enough. I wonder would the transmission ever get up to temp? Do you have a gauge to monitor temp?

As with my previous builds with only an aux cooler, one rock tossed up by the truck in front of you can end your day pretty quick. Yes, this did happen to me back in the day on a 79 Bronco I was driving on the gravel roads in MT. And since the Rad cooler was still in-service, I was able to bypass the Aux cooler.

I look forward to others commenting on your set-up with more knowledge.
 

spap

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I agree with the less points of failure, I use one 10x11 raditor cooler for my 4r70w and it works great right in front of the radiator. I do not use the radiator cooler I go in the Mohave desert in summers with hot temps and the trans temp has always been fine.
As points of failure. Do not use plastic heater hose connectors. They will break in the middle of the desert …….
 

Broncobowsher

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I see more problems. Lots of them.
The through core zip ties on the large cooler are not nice to the core.
The small cooler is mounted so far in front of the radiator and has no ducting, it won't provide any low speed cooling. What air the fan draws in will just flow around that cooler.
Mud and rocks, lots of convertor load, zero vehicle speed. You are relying on airflow for all transmission cooling.
Why the aversion to the in radiator cooler? To this day that is how nearly everything does it. The latest is an out of radiator oil to water heat exchanger. But it is still an oil to water heat exchanger, just more plumbing on the coolant side. I think a lot of these are being plumbed to put heat into modern transmissions that run a lot of convertor lockup to be more efficient. But a C4 doesn't lockup and just builds heat as the transmission slips.

I would run the in radiator transmission cooler and ditch the small cooler hanging out not being effective. Remount the big cooler to not be stabbing through the core.
If you still have an extreme aversion to the in radiator cooler you have, run an external oil to water cooler. Back in my overkill days I would probably come up with something like a remote engine oil filter adapter plumbed into the transmission cooler line, get a spin on transmission filter out of it as well. On that oil filter mount add an engine oil cooler sanwich adaptor (like the factory Explorer oil cooler, mustang SVO oil cooler, etc.). But where to feed it water? Tap the back of the intake manifold water crossover. This will be a source of water that has passed through the block but before the head. Warm, but not hot water. Then where to return it, Tee into the heater hose return into the water pump. Not going to be as good as the in radiator cooler, but will still give a heat dump into the coolant. Which is ideal at low/no speed high load use. Gallons of water has enough thermal mass to absorb thermal spikes.
 

Yeller

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I think the dual coolers is overkill but not a big deal, if makes you sleep better there’s nothing wrong with it. The only issue I see has been pointed out, that large cooler needs to be mounted to the core support and not with the supplied zip ties for your intended purpose.
 
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jeffncs

jeffncs

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Thanks to all for the input.

I have the fittings to make the radiator cooler work. I was just avoiding that option b/c really didn’t want to trust it. I’ll route to that first then through an aux cooler.

Should I just stop overthinking and remove the aux coolers entirely with sole reliance on the radiator unit? Or should I run the radiator plus the larger cooler mounted on the radiator unit but change mount design?

Side note - all lines and fittings are AN-6. No plastic at all.
 

Yeller

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personally I would forgo the radiator, just me. I get the warming effect, never seen a failure from running them cold, seen some in need of a rebuild not work well cold, but never a failure.
 

stout22

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I have had a radiator fail into the transmission side and ruin my transmission. It was a stock "brass" radiator.
 
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jeffncs

jeffncs

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Based on the advice of the forum and a trusted friend, I reworked the trans cooler and PS cooler.

Trans cooler: simplified the cooling system to the single, large cooler mounted to the radiator support. That eliminated the through radiator plastic clips.

PS cooler: I repurposed the aux trans cooler to be the PS cooler. I haven’t plumbed that yet but think it’s over I’ll…especially since I’m going to add a ram which will further increase the fluid in the system and heat dispersion. I have a small, 96-01 PS cooler that may be called into action.

i since trimmed the bolts and painted the brackets to blend them into the background.

Thanks to all for the input.

IMG_0594.jpeg

Thanks to @Yeller @stout22 @Broncobowsher and everyone else that contributed.
 

JSBX

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I am another one that lost a C4 transmission due to the cooler in the radiator springing a leak. pink milk shake in the transmission and in the engine. It was a brass radiator. I now run a stand alone cooler with fan mounted under the passenger side floor for my 4R70W. Works great. My son has been running the same set up for 8 years with no problems.
 

fordguy

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I am another one that lost a C4 transmission due to the cooler in the radiator springing a leak. pink milk shake in the transmission and in the engine. It was a brass radiator. I now run a stand alone cooler with fan mounted under the passenger side floor for my 4R70W. Works great. My son has been running the same set up for 8 years with no problems.
I am with James, bought the biggest Derale I could get. My rig is set up where I have a blue tooth connection to ECM and I can set my dashboard on forescan to see what live data o choose. Looking for a good iPad mount that will be bolted to the trans tunnel. Went with a US radiator (non aluminum). Our summers are equally hot.
 
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