Can you have too large of a trans cooler ??

[Gsragtop]

So I was walking out of my local wrecking yard, when I saw a truck with a nice aftermarket trans cooler just sitting there (front grill removed, easy access).. So I pulled it off to add to my kia.. Then I thought maybe it's too large ?? Could that cause issues with the trans as well ??

Also,on the truck it was mounted in front of the AC condenser. While this is an easy place to put it, would it not effect the AC performance ??

Thanks
Josh

[Golden_HVAC]

wgriswold wrote:
I have always thought it should be installed before the radiator so that if the fluid is cooled too much it will be warmed to the proper temperature before going back to the transmission. Others disagree.

What do you all think?

I had a 1985 GMC 3500 van motorhome. It had a 12,000 GVWR, and 350" engine. IT overheated all the time. The fan clutch would kick in at 95F outside air temp when the A/C was running on flat areas. I installed a digital temp gauge on the transmission, it ran at 235 on flat and level ground, got really hot in the hills.

So I had a 11" X 19" transmission cooler that I had intended to install on my pickup, but never did. No room in front of the radiator, and I did not want to warm up the air going into the A/C condenser anyway. So I had 4" between radiator and fan blades. I think a main reason for not mounting it here is if the straps break, it will get destroyed by the fan!

Anyway I ran the transmission fluid into the oversized cooler and then into the radiator tank. I figured I did not want cold fluid in the winter collecting water condensation. My temps on the next trip was around 200 on flat land and 235 in the mountains. So I re-installed the factory 'tiny' cooler after the radiator, then I had cool transmission. I also think that the 250+ fluid leaving the transmission was cooled down substancially by the first cooler, then went into the 'lower' radiator tank at say 175F. At this point, the coolant might have been warmer on a mountain grade, and it could take away heat. Then go through the final cooler, and back to the trans at say 135F, and cooled it very effectively.

Because the primary transmission cooling was the first cooler, and it was not dumping 50,000 Btu's of heat into the lower radiator tank anymore, the engine did run a bit cooler, and the fan clutch did not come on nearly as much. (the clutch brings the fan up to engine RPM and it roars while quickly cooling the engine, then goes back to 'idle' to save energy and not consume 5 HP moving air through the radiator as quickly.)

So I would be piping the larger cooler first, then the radiator, then to the factory air cooler (if you had one) or just straight back to the transmission from the radiator.

I bought the towing package with my Ford Edge, it comes with larger radiator fans, increased size transmission oil cooler, and tow bar. I did it for the increased cooling capacity, not any other reason. I did not plan on towing anything with it, but have towed some small trailers since that time. Nothing as large as yours though.

The frontal area on a camping trailer can put a lot of strain on the towing vehicle. 60 square feet of frontal area is like pushing a brick through water, it will consume a lot of horsepower. Don't forget to slow down a bit when pushing into a headwind. It will not hurt to take another 10 minutes on each 50 miles you are driving, but to go fast, it might overload the transmission and it's clutch pack!




Good luck with your project!

Fred.

[Turtle_n_Peeps]

Yes, you can cool the tranny fluid too much. If you don't have a thermostat it can keep the ATF too cold and not burn off the water. That is why OEM putters don't lock the converter up for several miles. They want the ATF to come up to temp.

[marcsbigfoot20b]

My 2000 Ford F350 dually Crew cab long bed with the 7.3 diesel had the small Trans cooler after the radiator cooler. By the time they went to the 6.0 motor they had figured out they needed a much bigger cooler.
I installed this 6.0 cooler in my 7.3 and it is 4 times bigger and made a 50 degree difference.....important since I live in AZ.

[TNRIVERSIDE]

DougE wrote:
wgriswold, That was always my thought and at one time it may have been accepted practice. Nowadays it's vehicle radiator first and auxiliary cooler second. Auto manufacturers seem to be more concerned about overheating than running too cool. I think, and maybe someone can confirm, that modern automatic transmissions now have temperature sensing that recirculates the fluid until it gets warm before allowing it to go to the cooler.

I know that my 09 F150 does have a thermostat inline with the transmission cooler. Also there are different size coolers. Apparently the size of the cooler is dependent on the towing package ordered.

[DougE]

wgriswold, That was always my thought and at one time it may have been accepted practice. Nowadays it's vehicle radiator first and auxiliary cooler second. Auto manufacturers seem to be more concerned about overheating than running too cool. I think, and maybe someone can confirm, that modern automatic transmissions now have temperature sensing that recirculates the fluid until it gets warm before allowing it to go to the cooler.

[wgriswold]

I have always thought it should be installed before the radiator so that if the fluid is cooled too much it will be warmed to the proper temperature before going back to the transmission. Others disagree.

What do you all think?

[mbopp]

Many newer vehicles won't let the torque converter go into lockup until a minimum temperature is reached. Probably not an issue in SC.

[ScottG]

It's possible but doubtful. The only time it would be too big is iff you were unloaded and the trans temp never got up to 140 degrees. In that case the fluid wouldn't burn off moisture and may get contaminated.

[Marauderer]

Josh, on my 07 GMC Sierra the trans cooler is mounted in front of the A/C cooler which is in front of the radiator. I think most vehicles are that way. As to the oversize, I have an oversize one on my truck. Do i need it in the cooler weather, NO. Do I need it in the summer when towing up long upgrade and backing down on long downgrades, Yes. Maybe you need one maybe you don't. You need to research it more. How is your TV doing now?