Z7What

For the people that say until you get over 2XX degrees don't worry about it. Well what the hell is he supposed to do when he does see this 2XX degree temps, pull over?

As its been said these trannys have thermostats. I can't confirm nor deny if this is true, but if it is true then adding a larger cooler wouldn't affect the daily driving temps but it would prevent the the temps from getting to this 2XX degree mark.

As for replacing the factory cooler with a larger factory cooler, it's not going to happen. Reason for that is that Ford doesn't make a larger one. It doesn't matter if you have a 2WD Single Cab, Raptor, HD F-150 with Max Tow there all the same size cooler.

From my research I have found a picture of a truck with a larger OEM cooler but unfortunately the image I have is a prototype diesel F-150 from years ago. Not sure why Ford has the tabs for installing a larger one.

On a side note why would Ford put a thermostat in the tranny and require it to run high 190s? That just doesn't make since to me, I know the fluid should be warm but 196 (what mine runs at) just seams to high to me.

https://www.f150forum.com/f38/bigger...cooler-266856/

Wayne

acadianbob

It sounds like you are determined to go your own way. But, the others are correct. The transmission is thermostatically regulated and designed to run at 195 degrees.

Feathermerchant

The thermostat causes the trans temp to get to the proper level fast then keeps it there. This makes the trans last longer and makes the truck get better gas mileage. It does make it a little harder to judge when the trans will overheat. When pulling a heavy load especially at low speed with the torque converter unlocked, you will have to monitor the trans temp closely. If it starts to rise from normal, that is a sign that it is generating more heat than the cooling system can deal with and you should slow down or take other action to reduce the cooling required. If the trans temp continues to rise, you should stop completely at the first safe opportunity and let it idle in park to cool.

PerryB

The reason behind the higher temps is to keep the fluid "dry", keeping moisture/condensation out of the transmission. I see a similar problem in aircraft engines (Lycoming ). Inadequate oil temps cause condensation to build up in the top of the case and the cam will corrode. Modern transmission fluid can go to 240°f without degradation.

Feathermerchant

PerryB - Certainly true.

Having the oil at temp soon also makes it thinner hence better gas mileage.

PerryB

That makes sense. Thinner oil pumps easier.

MSteven

Thanks for all the replies folks.
So, in the new world of synthetic grade lubricants, the old rules are now invalid, Got it.
A thermostat to get it to operating temperature makes sense. Especially for the reason above.
This is reassuring, I guess I'l just run it like it is for now.

More later.

redneck wrencher

Unless you are constantly seeing trans temps above 220*, I wouldn't fret too much. Older Mercon fluids had an "ideal" operating temp of 170*. Coming from the 7.3 diesel world, most would get excited when temps climbed above 200*. Newer synthetics, such as the LV, and improved clutch materials are capable to seeing peak temps of 300* and still function for their service life. This statement comes from an ex Ford trans engineer I know. Times are changing and we need to get up to speed. I did my research when, and after, purchasing my F150. I haven't seen any towing temps that have gotten me excited.

kmlacroix

There was specs for a larger aux trans cooler for the HDPP, but there is no part number for it.

redneck wrencher

Through some research, I have found there is a larger, optional Ford trans cooler (7L1Z7A095B). It was used on the 2007-8 and 2015-16 Expeditions and Navigators. It is a 6 row versus the standard 4 row on the F150's. It looks to be a direct replacement for the F150 and fits the stock mounting bracket; with only having to shorten the upper side hose slightly and trimming off a couple of plastic tabs. There is about 1'' difference in height, but is a 50% increase in capacity for its size.