MSteven

My 2011 F-150 5.0L w/3.55 axles and a regular tow package, not max tow, needs a larger trans cooler.
Looking at the cooler mount it appears that a much larger cooler will fit on it.
I remember some discussion about retro-fitting a larger cooler, but can't find the thread(s) where it had a definitive answer as to what cooler(s) fit on the mount.
Does a cooler from a Super Duty fit?
I pull a 5200 lb. travel trailer and plan on pulling across the continent, meaning mountains and a lot of headwind.
At 60-65 mph the cooler temp reads 195* on the flat at 1200ft. elev.
This was in fairly cool weather, mid 40's to 50's.
This is with Tow Mode on and 6th locked out.
I just know someone has a definitive answer for this.
Is there an aftermarket cooler that's a better choice than using a Ford cooler?

smokeywren

You don't need more tranny cooling capacity unless you often see over 210° on the tranny temp gauge. Even then, watch that gauge closely and don't worry unless the tranny temp gets up to 225°. 225° is the red line, so don't allow more than 225°.


There is only one OEM heat exchanger (tranny cooler) available for your 2011 5.0L tranny. That one came with either the regular tow pkg or the max tow pkg or the heavy duty payload pkg. So there is not a bigger plug&play cooler available from Ford.
http://parts.autonationfordwhitebear...il-cooler-scat


If you go for an aftermarket cooler, then you must figure out how to mount and plumb the new cooler to replace your OEM cooler. No, the famous Ford OEM cooler from a 6.0L diesel won't fit without a lot of shade tree mechanic and fabrication skills.

So I'd run with what Ford brung until you notice tranny temps close to 225°. If you frequently see over 210° but not over 225°, then you might consider upgrading to an aftermarket or 6.0L cooler, after you understand the difficult job of mounting and plumbing the new heat exchanger.

MSteven

At the speed/flat ground/1200ft elevation and low ambient temps 195* sounds high. Summertime temps, and pulling Rocky Mountain grades it will be far higher, and that has me concerned.
I'm pretty handy, so retrofitting doesn't scare me. I'm just old and smart enough not to make things harder for myself. If there was a factory part swap, I'd be all over it.

smokeywren

The Ford engineers don't agree with you. Beginning with the 2011 model year, the automagic tranny is designed to maintain the tranny temp at a minimum of around 190° to 195°. Adding a larger heat exchanger to the tranny cooling system will not change the computer program that controls the tranny temp.



Don't be concerned unless you actually see over about 220° tranny temp. The tranny cooling system is designed to handle trailers that can weigh enough to reach the GCWR of the truck on steep hills or mountain passes. But if you get close to the GCWR, you'll be severely overloaded over the payload capacity of the F-150. If you don't overload your F-150, then you shouldn't have any problem with an overheated tranny, even when climbing Wolf Creek Pass. But watch that gauge anyway, in case your tranny cooling system has a glitch in it.


There is no Ford part, but you can fab up a way to mount a much bigger heat exchanger. Way back in the '99 thru the first half of the 2001 model years, the F-250 diesel with 4R100 tranny didn't have a big enough heat exchanger to handle the job on steep grades. When the engineers tested the tranny cooling system to set the GCWR, they climbed steep grades at 100° or more, but they climbed at a fast enough speed to have a locked torque converter. But lots of customers climbed similar grades while poking along with an unlocked torque converter, which sends a volcano worth of heat to the tranny cooling system, overpowering the tranny cooling system.


Some folks added a huge heat exchanger under the cab, and that worked. Then Ford had a program to significantly increase the tranny cooling capacity for anyone that requested it. I requested it and they swapped out my ordinary huge radiator for one that included an oil-to-water (OTW) heat exchanger in the bottom of the radiator, plus plumbed it to use both the OTW and oil-to-air (OTA) coolers. Beginning with late-2001 models, both coolers were standard in the Ford F-250 diesels. But some folks still weren't happy, so they replaced the OTA cooler with the much bigger one from a 6.0L diesel. No more problems with tranny overheating.

I've heard no reports of anyone actually overheating the Select Shift automagic tranny in 2011-up F-150s. Some folks are concerned that the normal operating temp of 190° to 205° is high. But notice the analog idiot gauge on your dash. 205° will not get the gauge close to the yellow zone on the gauge. If you ever see the gauge jump into the yellow zone, then look at your digital gauge and you'll probably see 225° or more, then it's time to shutter down and cool off.


Yeah the idiot gauge is weird. The white zone means you're good to go. The yellow zone means your tranny is overheated. And the red zone means your tranny is probably toast.

Bigdog364

2011 f150 screw. Changed out transmission after 238,000 miles. Never got over 200 degrees. The fluid comes from the tranny to the oem cooler then goes thru the radiator on the way back to the tranny. Coolant is at 195 degrees set by the thermostat. The trans fluid temp will be the same. I installed a Hayden 679 trans cooler and the temp was 195 degrees. Normal range. I put in a used "30,000 mile" 2014 6r80 4x2 and its temp is 195 degrees.

Feathermerchant

There is a thermostat in the transmission that seeks to maintain a constant transmission temperature. I think it is 195.

MSteven

Having worked on some complicated hydraulic systems in my career, it's been my experience that high temps are the number one cause of failure.
In running 70mph for 75 miles in the same trip, the trans temp showed 205* at one point. I slowed to 65 and it dropped to 197* and eventually 195* at 60.
I have no idea what the specs and properties of the synthetic transmission fluid in mine are, but it'd take some convincing for me to accept 195* wouldn't translate to 210*+ pulling a 6% grade to 10,000 ft. in 90* heat, and it toasting the fluid in a short time.

smokeywren

ATF has improved dramatically over the last 20 years. Whereas it used to be published that ATF began deteriorating at 175° F., the synthetic ATFs now available can hang on to over 210° without deteriorating too much in 20,000 miles of towing.


Way back in my 1999.5 F-250 diesel with 4R100 tranny, I ran Mobil 1 ATF and changed it every 20,000 miles. I towed my 8,000-pound 5er over just about every mountain pass in the lower 48. I had a good tranny temp gauge that showed sump temps, and I never saw over about 215°. That tranny was still going strong at 112,000 miles, when the torque converter began rattling, so I had the tranny "bullet proofed" by BTS. I later sold it with 197,000 miles on it, and last I heard it now has over 300,000 miles on that BTS tranny.


My scheduled maintenance guide for my 2012 F-150 with 6R80E tranny says a tranny fluid change is not required until 150,000 miles, regardless of towing or not. That's a lot longer than the 30k miles when not towing and 20k miles when towing for my '99.5 F-250 with 4R100 tranny. So it sounds like MERCON LV has a lot longer lifetime than plain ole MERCON had 15 years ago.

My 2012 F-150 requires MERCON LV ATF, which is Ford spec XT-10-QVL. I cannot find a definitive spec that tells whether that is dino, synthetic blend or full synthetic ATF. So I'm hoping that Ford (Motorcraft) did a better job in formulating MERCON LV than they did the original MERCON. But I'm betting that MERCON LV can live at least 20,000 miles with tranny temps up to 225°.

Feathermerchant

I drove a 5 hr trip last night in ~60 deg F ambient 70-80 mph not towing and saw 196 deg F trans temp. So I'd say that is normal trans temp.

PerryB

There certainly is no harm in a bigger cooler, but you won't see a reduction in your cold weather/low load temps because the transmission temp is controlled by a thermostat.