I have and 8” on 37”s I need to get a bigger trans cooler but can I keep my old trans cooler in there and get a 6.0 cooler and run the stock and put the the 6.0 coolers the very front and run then together?

 

 

You don't want too many coolers because it adds restriction and you'll end up with less cooling.

The right way to do it is to run from the front of the trans to the radiator cooler, then to the 6.0L cooler, then to the rear of the trans.

 

Yep the 6.0 cooler will do you well. I have that and extra deep trans pan and run 140 tops through the heat of summer in FL unloaded. Towing I have seen 165 max. I have 6” on 35”s so pretty close to your set up, before the 6.0 cooler I would run up the temp quick.

 

 

E99- late 00 had no transmission radiator cooler, they just ran the lines from the transmission to the trans cooler.

 

Hot line from transmission > radiator cooler (assuming you have it) > then to 6.0 cooler > back to return line of transmission. Make sense? I didn't use the radiator cooler.

 

The 6.0 Cooler does great by just removing the 7.3 cooler and mounting the 6.0 in its place.
I believe Mark was just describing the proper fluid flow from the transmission, to the radiator cooler, through the trans cooler, and back to the transmission.

 

 

 

What, if any would be the downside of going through the 6.0 cooler before the radiator?

 

Water is a more efficient heat transfer medium than air, so water can wick the highest heat out of the transmission fluid faster.

Since the "water" in this case is engine coolant, the engine coolant is already at an elevated temperature, so engine coolant will be most effective in wicking away heat in the transmission fluid when the transmission fluid is significantly hotter than the engine coolant. The greater the disparity between transmission fluid temperature and engine coolant temperature, the more dramatic the effect the oil to water cooler will have at reducing the transmission fluid temperature during the brief pass through visit. If both fluids were at the same temperature, no heat transfer would take place. Equilibrium would already be close to parity.

There is only so much time that the transmission fluid has to dwell in oil to water cooler. The cooler is only a foot long, and the transmission fluid is (hopefully, at minimum) flowing at a rate of at least a gallon per minute. Not much time to take advantage of the thermal transfer efficiency of water immersion.

Even if it is 120 degrees F out side in the middle of August in Arizona, we know that this air will still be cooler than the 200 degree F engine coolant once the truck is at operating temperature. And, we also know that the 6.0L oil to air cooler, while much, much larger than the oil to water cooler, is still limited in it's ability to drop the temperature of it's temporary contents by the amount of time the transmission fluid remains resident in the cooler. Therefore, there is some limit as to how much the oil to air cooler can reduce the temperature. Call that limit x.

If the transmiission fluid enters the oil to air cooler after already having been somewhat cooled by the oil to water cooler, then the fluid enters at 1, is reduced by X, and the output yield temperature leaving the oil to air cooler will be y.

However, if the transmission fluid enters the oil to air cooler directly from the torque converter of the transmission, when the fluid is at it's absolute hottest, without benefit of any oil to water cooler pre cooling, then let's say the fluid enters the oil to air cooler at 2, is reduced by x, and the output yield temperature leaving the oil to air cooler will be z.

Without knowing the values of x, y, or z, we can clearly see that if x (the capacity of the 6.0L cooler to dissipate heat) is fixed, then output z will be greater than output y, because the entrance temperature 2 is greater than the entrance temperature of 1.

If I had a smoldering hot blob that was 300 degrees, and I had caldron of boiling water that was 200 degrees, and a room with a fan on that was 100 degrees, and I was allowed to use both the caldron and the fan to cool the hot blob, but only for a limited time with each method, and only in series one after the other, and I had to choose which cooling method to employ first... Then I would chose to first dip the 300 degree blob into the 200 degree caldron, so that the 300 degrees could cool down to 225 degrees before putting the blob in the 100 degree room with the fan.

 

Exactly. This is why it is more efficient to put the radiator cooler ahead of the 6.0L cooler. You'll end up with cooler transmission temps this way.

That isn't the temperature of the coolant inside the radiator. The transmission cooler is in the tank that collects the coolant AFTER it passes through the radiator. So it's cooler than engine temperature. If it was still at engine temp in this tank you could just delete the radiator because it isn't doing anything.

 

Well, leave it to the actual engineer, whose job it was to instrument and test Ford automatic transmissions, to point out the obvious "duh" that I missed. Yes, the tank on the bottom of the radiator is swirling with coolant that has already passed through the radiators cooling core. This fact further increases the initial temperature differential between the trans fluid and the coolant... all the more reason to make the oil to water transmission cooler first priority.

It's like taking my 300 degree hot blob and dunking it into a 150 degree caldron of water, instead of a 200 degree caldron. The cooler water, and the greater initial temperature difference between my glob and the caldron water, enables more heat transfer.

Then I'd have a cooler glob to start with before putting it into a 100 degree room of air with a fan on for a minute. Since it can only stay in the room a minute, and since it has been established that air is a lot less efficient at transferring heat than water, I'm better off putting as cool of a glob as I can, to make the most of the efforts of the room and fan.

 

Wow, great responses!

I have mine plumbed through the 6.0 first and I’ll probably leave it that way. I’m running too cold as it is and I figure going through the radiator sencond might help keeping it from running even cooler. I usually see 125 empty, 150 loaded and worst case was pulling 12k in 100 degree weather at 175. I think a thermostat is in order.