Microreedy

Any ideas on a transmission oil cooler, hoses, etc for a 500 hp olds 455. Would like to mount with electric fans to be more efficient than stock application. My radiator threads are stripped so I will be bypassing the radiator if possible.

oldcutlass

I don't know your location. The radiator trans cooler actually serves 2 purposes it cools in the summer, but also warms in the winter. Not running the cooler through the radiator may not allow the transmission to reach a good warmed temp in the winter.

Professur

Take out your radiator, take it to a radiator shop and have new bungs welded in. You need the heat from the engine coolant to maintain and regulate the transmission fluid temp. When you install an aux trans cooler, you install it before the radiator so that it can dump the most heat, then get rewarmed back to operating temp before it's sent back to the transmission. Failure to get the order right will result in excessive transmission wear and early failure.

Gotta ask, how did you bugger up the threads in the rad in the first place?

ELY442

That's what I did. My radiator guy closed down during the 2008 recession and my trany oil was leaking by the radiator bung. So I installed a auxiliary cooler bypassing the radiator and mount it in front of my grill with the attaching kit. No problems so far.

droldsmorland

For what its worth I too thought the air over oil auxiliary cooler was better off located BEFORE the primary radiator cooler until I locked (friendly) horns with a transmission engineer for Ford. Mark is a well respected Trans engineer on FTE.com

For years I thought I had it correct from my training and looking at what I've seen on other "Knowledgeable" wrenches rides over the last too many years than I will admit to......

My original post with what I thought was correct information...

My Original Quote:
"Also keep in mind, too cool for a trans isnt good. A trans likes to be at its rated op temp range. The myth that cooler is better is just that. A trans cooler is there to maintain temps and avoid spikes. (This much is true).
I've seen some who insist on plumbing the secondary cooler after the primary (in radiator) cooler. That configuration can prevent the trans from ever getting to op temp. Always plumb the secondary cooler ahead of the primary. This orientation will allow the initial excess heat to be rejected before it hits the radiator. The radiator(primary) cooler will reject or induce the remaining differential thus not dumping heat into the radiator which wont do the engine any good and it will put heat back into the trans if what came out of the secondary cooler was too cool. I agree with Mark 3 coolers is not a desired set up for your situation". (OP wanted to plumb in 3 coolers).

Mark picks me apart:

My Quote:
Originally Posted by droldsmorland
I've seen some who insist on plumbing the secondary cooler after the primary (in radiator) cooler.

Marks reply:
Yes, I'm one of them. And so is Ford Motor Company, GM, Chrysler, and all of the imports, too. Every factory cooling system I've ever looked at had the air to oil cooler AFTER the radiator. And I looked at many, many of them. It was part of my job as a transmission cooling engineer to analyze the competition.

My Quote:
Originally Posted by droldsmorland
That configuration can prevent the trans from ever getting to op temp. Always plumb the secondary cooler ahead of the primary. This orientation will allow the initial excess heat to be rejected before it hits the radiator.

Marks reply:
The system is more efficient when the radiator cooler is first. This cooler removes most of the heat from the ATF, then the air to oil cooler can lower the temperature further.

My Quote:
Originally Posted by droldsmorland
The radiator(primary) cooler will reject or induce the remaining differential.

Marks reply:
WRONG. The radiator COOLER will never warm the ATF. Ever. In any condition. I measured this in ambients ranging from -48F to +121F and I NEVER found a condition where the radiator COOLER warmed the ATF. I know many people believe it does, but I collected reams of data proving otherwise.

My Quote:
Originally Posted by droldsmorland
thus not dumping heat into the radiator which wont do the engine any good and it will put heat back into the trans if what came out of the secondary cooler was too cool.

Marks response:
Here's one scenario from ACTUAL testing.

The ambient temp is -40F. Everything in the vehicle is -40F. You start it and start driving. The engine will come up to temperature in several miles, and the thermostat opens. It sends 200F (nominal temp) coolant into the radiator, while replacing the coolant through the lower hose with coolant that has been sitting in the radiator. It's still -40F. The engine cools FAST and the thermostat closes. The flow in the radiator stops. From actual measurements the hot coolant never gets close to the cold side of the radiator. The radiator rejects that heat and by the time the coolant gets to the transmission cooler it's -40F again. Meanwhile the transmission is working, so it's temperature is creeping up. By the time the thermostat opens the first time the trans may be sending ATF to the radiator heated all the way to 0F. Now how well will that -40F coolant add heat to the ATF at 0F? Answer: It can't, thermodynamics says that's impossible.

And I've driven cars and trucks for a long time and in cold weather that scenario just repeats over and over. The coolant NEVER warms the ATF. Ever.

And the engine radiator is sized to cool the engine along with the transmission heat load.
__________________
Mark
Former Ford Automatic Transmission Engineer 1988 - 2007

“The good thing about science is that it's true whether or not you believe in it.” ― Neil deGrasse Tyson


Moral of the story, shut pie hole open ear holes...never too old to learn. I guess the only question would be is there a difference between OEM and High Perf? I don't think so.