Transmission Coolers

[slvrwrx]

I didnt like how the radiator was the main cooler for my transmission, but then it went into a secondary cooler in the grill. I went to the junk yard the other day and found a nice oil cooler. I rerouted transmission lines to piggy back from the stock grill cooler into the secondary grill cooler i installed, then back to the transmission. Im seeing 130 degrees on my gauge.


Im trying to get back on the forums, I lurk more than anything these days, cause my computer sucks and I usually use mobile version. Pics to come..

 

[homelessduck]

It might not be a problem where you are, but part of the reason for the trans. fluid to run through the rad is to help keep it at operating temp. In cooler climates, without it running through the rad , the temps will be much lower than the ideal operating temp which is bad for a trans...

 

[slvrwrx]

That makes sense, however i dont see the point in having the secondary auxillary cooler then. My climate is pretty mild in the bay area, ca. I noticed right off the bat my transmission feels alot more solid, and the shifts are positive.

 

[LCAM-01XA]

That makes sense, however i dont see the point in having the secondary auxillary cooler then. My climate is pretty mild in the bay area, ca. I noticed right off the bat my transmission feels alot more solid, and the shifts are positive.

Have you ever seen close to 300F on the converter discharge line? You'd know then why the factory liquid heat exchanger and the auxiliary air cooler are plumbed in series

Basically yes the cooler in the radiator helps in warming up the transmission but only to a point - once everything is at normal operating temps the coolant in the radiator is cooler than the fluid running thru the trans cooler, so heat is pulled away from the trans fluid at some pretty good rates. Then the aux cooler sheds some more heat, especially if it's blown by a small e-fan (bonus points if the e-fan is on a temperature switch). The bigger the aux cooler and its fan the cooler the trans fluid headed back to the slushbox. But an aux cooler alone has to be pretty massive to shed all the heat a non-locked torque converter can generate under heavy load, what you have now is very likely not to keep up. A repurposed air-conditioning condenser with big lines feeding it and a locked engine fan behind it has little problem overcooling the trans. But for best results run both the factory cooler and the aux stuff.

Another thing to consider is the restriction two big aux coolers plumbed in series present to the flow of the trans fluid. The longer the path the fluid has to travel the higher the "friction" between it and the walls of the tubing it flows thru. To avoid that, consider replumbing the two coolers in parallel - split the cooling lines you have now with T-ee fittings and let fluid run thru both coolers at the same time as opposed to first thru one and then thru the other.

 

[OLDBULL8]

I think LCAM-01XA should have said Parallel instead of Series with the Aux coolers. You want all the volumn you can get back to the trans, most return oil is used for bearing lube and cooling. If most of the bearings have been updated to Ball and Needle bearings (Torrington Thrust) instead of Bronze bushings and Bronze thrust bearings that's a Plus as they don't run as hot.
If you do a lot of heavy towing, the 6.0 PSD Aux cooler is the Cats Ass for that, Whoops Cats Meow.

 

[icanfixall]

Sp from your pics this engine was a ford rebuild and its from a van application too. But why are you not running a radiator fan shroud?? Those are very important to cooling properly.

 

[LCAM-01XA]

I think LCAM-01XA should have said Parallel instead of Series with the Aux coolers.

Nice catch, I edited the post to correct for that, thanks!

Also yes, shroud around the fan makes a huge difference, get one ASAP or you may end up in a rather undesirable situation next time you decide to pull up a nice long grade that goes on for miles and miles...

 

[Knuckledragger]

If you tow much, you might consider installing a deep trans pan. Not only do you get extra cooling from the fins on the bottom, you have another quart or two of volume to allow the operating temps to stabilize (or at least not skyrocket). More fluid in the system is your friend all around.

 

[FORDF250HDXLT]

that looks like you scored a really nice aux cooler.im in agreement with plumbing in your primary water cooler then running the aux down the line.this way here,you'll have cooling even at idle and slow speeds and the aux will shed off anything extra ya need when towing/hauling.

"According to Ron Sessions, author of the Turbo Hydra-Matic 350 Handbook (HP Books), the ideal operating temperature for transmission fluid is between 175 and 225 degrees Fahrenheit."

 

[trackspeeder]

It might not be a problem where you are, but part of the reason for the trans. fluid to run through the rad is to help keep it at operating temp. In cooler climates, without it running through the rad , the temps will be much lower than the ideal operating temp which is bad for a trans...

The radiator will never heat the oil. It will always cool it. The tranny will reach operating temp long before the coolant. This is why the cooler is located at the bottom.

The reason for this cooler is for low speed operation and reverse. This is where oil to air cooler will fail do to lack of air flow. Having a liquid to liquid cooler as a primary cooler will prevent this problem.

 

[OLDBULL8]

If you tow much, you might consider installing a deep trans pan. Not only do you get extra cooling from the fins on the bottom, you have another quart or two of volume to allow the operating temps to stabilize (or at least not skyrocket). More fluid in the system is your friend all around.

I kinda disagree with that unless your traveling on a snow covered road. A 2wd has about 2 less quarts than a 4x4 pan. Measureing temp with a non contact Laser meter, there is only about 5*F difference from top to bottom on a 4x4 pan. I monitor my trans temp from the pressure test port, that's oil directly from the pump, my oil goes thru the radiator, then thru a tru-cool 42K aux cooler, unloaded I run ~170*F, loaded with my 5er, 13000 lbs, I run ~ 185*-190*. On a long 6-7% grade, I run 210*.

 

[LCAM-01XA]

The radiator will never heat the oil. It will always cool it. The tranny will reach operating temp long before the coolant. This is why the cooler is located at the bottom.

Not always tho - our POS would push coolant thru the radiator within 10 min of firing up the engine even while idling in "Park", whereas the E4 would still be debating what it wants to do

 

[snicklas]

Also, I remember Gary (icanfixall) said he had discussed the deep pan with Brian at BTS when he bought his E4OD from him. Brian advised against the deeper pan, because the airflow over the pan doesn't help cool much at all. Also, the fluid does take longer to heat up, because there is more if it, but that also means it takes longer for the fluid to cool back down after a heatsoak...... I think Brian recommends using the 4x4 pan, vs one of the high-dollar pans........

Hopefully Gary will see this shortly.........

 

[Knuckledragger]

Also, I remember Gary (icanfixall) said he had discussed the deep pan with Brian at BTS when he bought his E4OD from him. Brian advised against the deeper pan, because the airflow over the pan doesn't help cool much at all.

OK, what does that really mean? I never said it was a replacement, just that it would help with cooling.

Also, the fluid does take longer to heat up, because there is more if it, but that also means it takes longer for the fluid to cool back down after a heatsoak...... I think Brian recommends using the 4x4 pan, vs one of the high-dollar pans........

Hopefully Gary will see this shortly.........

I looked at my (c6) 4x4 pan and it does indeed have a little more depth than a 2wd unit. I guess high dollar is a relative term, my cast aluminum finned pan cost about $65 and holds 2 extra quarts. A 4x4 pan is still stamped steel which will not help with cooling at all but does cut down on space, if that is a concern. I did say that more volume will stabilize the temps. Warmup time is not an issue unless you are storing the truck outside in sub zero conditions. Warmdown should also not be an issue, since the truck is presumably sitting still.

 

[homelessduck]

The radiator will never heat the oil. It will always cool it. The tranny will reach operating temp long before the coolant. This is why the cooler is located at the bottom.

The reason for this cooler is for low speed operation and reverse. This is where oil to air cooler will fail do to lack of air flow. Having a liquid to liquid cooler as a primary cooler will prevent this problem.

Just relaying information that I was told on here about a year ago when I had a very similar question.