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Auxiliary Transmission cooler

Colo_Ranger

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Alright - I drove to Beaver Creek and my transmission was sitting at 215º F for a long time. That's too high, in my opinion, so I am looking for a transmission cooler. Before I go reinventing the wheel, has anyone installed a transmission cooler on their Ranger? Google is not returning any direct fit options so I am going to need to start looking at universal and custom mounting options.
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Frenchy

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I don't recall if anyone has made an external cooler for the Ranger, but I am aware that these will run a bit warm compared to others. Why? Because here at Ford Motor Company we have Better Ideas than you and we know it!
 

KTM0620

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Grumpaw

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215 is actually what Ford considers to be normal operating temps. I was informed that Ford dosen't consider taking a proper fluid level measurement until temps reach around 210. The fluid temps are not considered "hot" until around 235 degrees. Its a fully synthetic fluid....not like the "olden days stuff".
When I had my Ranger, towing in mountainous areas during hot months, me Scan Gauge lll regullarly read 210 + for short periods, until the down slope....and in 4 years of towing, never had a tranny problem.
My current 2019 Expedition has the exact same 10R80 trans, and when towing our trailer has hit 205-210 on occasion....not as often as the Ranger, but I attribute that to the extra 125 hp/extra torque..... that means the Expy dosen't have to work as hard as the Ranger to pull the same weight.
My one question.....was the 215 you saw while the rig was "working" or while running solo on the highway ????
I'm not saying don't install a cooler....do what you think is best for you........just sayin 215 is not overheating.
 
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TJC

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Alright - I drove to Beaver Creek and my transmission was sitting at 215º F for a long time. That's too high, in my opinion, so I am looking for a transmission cooler. Before I go reinventing the wheel, has anyone installed a transmission cooler on their Ranger? Google is not returning any direct fit options so I am going to need to start looking at universal and custom mounting options.
I'm preparing to attempt to install a transmission cooler on my 2020 Ranger. Ford does say to measure at 206F-215F to get the correct fill, but I think thos temps are far too hot, and shorten fluid and transmission life. GM has a sister transmission to the 10R80, and they run it at 150F-165F. Basically 90% the same as the 10R80.

Before I get push back on this, Ford also says you don't need to change the fluid for the life of the transmission... and I don't beleive that either. Here is what came out of my trnsmission at 18K miles (and I babied it). Black as coal!

DSCF0170.webp


There are two ways to go about cooling down the transmission. The simplest way is to allow engine coolant to run through the heat exchanger all the time and install a 170F engine thermostat. The engine and transmission with stay in the 180F - 190F range.

There are 3 coolant hoses on the heat exchanger. You simply need to bypass the thermostat and go directly to the heat exhanger. There are 2 coolant hoses going to the heat exchanger. 3 going to the Thermostat controlling the coolant flow to the exchanger.

A = The electrcially controlled thermostat
B= Heat Exchanger

You want to bypass the thermostat entirely. And route the in/out coolant lines from the thermostat down to the heat exchanger. Protect the thermostat ports by installing coolant caps in case you ever want to reverse the change. Keep the thermostat electrically connected to keep from throwing an error code. It will still open and close, but won't do anything, as no coolant will be flowing through it.

The 2 hoses going to the engine are the ones you want to reroute to the heat exchanger. Pick up a brass nipple or two with hose clamps if you wish to use the existing hoses.

It is not difficult, but the area is tight to work in.

10R80 Cooler Image 3 .webp


The 2nd method is more comprehensive and the one I am going with. I'm going to install a transmission cooler behind the front grill and bypass the heat exchanger completely.

You'll need this adapter to replace the heat exchanger.

Trans Adapter 2.webp
Trans Adapter 1.webp


Then run a pair of AN8 PFTE hoses to the cooler.

I expect to see temps staying between 150F - 165F. I really won't know until I complete the project.

I will probably start the work this spring. I have all the parts. Just waiting for slightly warmer weather.

Expect to pay $350 - $500 for the parts and tools to do the job. The adapter along was $100. A good quality cooler will run $150, then it is hose and AN8 fittings.

Routing the hoses and mounting the cooler will be the tricky part. I'll pull the grill to see what kind of room is available, then I'll need to fabricate a bracket to mount it. I want it a couple of inches from the AC Condenser and Radiator.

I don't know if this helps you any, but this is my analysis of the possible options, and my plan.
 


PltFX4

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@TJC not sure I under stand the gain here. Normal operating temp for the Ranger is 190° F to 230° F. Using the heat exchanger under the right conditions will be a gain but often a push... the engine coolant will be hotter that the trans temp, rising rather than lowering it.

Two on my other cars use that same exchanger with coolant/engine oil as the two exchanging heat. The one car group is a fan of removing it altogether and there is a block off kit to replace it. (and this car is a 6-speed manual)

I like your second approach more... but now the issue is does the rans get hot enough?? Will there be a thermostat in the circuit to regulate the temp? The other question: I don't have any idea of what the line pressures are in those trans lines to the radiator, will you need a "special" (ie: purpose built) type of radiator to handle it??

On my other car that is an automatic, I am considering using a Audi trans cooler with built in thermostat... line pressure on it are typically in the 30 psi, up to 60 psi.
4b0317021c.webp
 

TJC

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@TJC not sure I under stand the gain here. Normal operating temp for the Ranger is 190° F to 230° F. Using the heat exchanger under the right conditions will be a gain but often a push... the engine coolant will be hotter that the trans temp, rising rather than lowering it.

Two on my other cars use that same exchanger with coolant/engine oil as the two exchanging heat. The one car group is a fan of removing it altogether and there is a block off kit to replace it. (and this car is a 6-speed manual)

I like your second approach more... but now the issue is does the rans get hot enough?? Will there be a thermostat in the circuit to regulate the temp? The other question: I don't have any idea of what the line pressures are in those trans lines to the radiator, will you need a "special" (ie: purpose built) type of radiator to handle it??

On my other car that is an automatic, I am considering using a Audi trans cooler with built in thermostat... line pressure on it are typically in the 30 psi, up to 60 psi.
4b0317021c.webp
I am bypassing the heat exchanger completely. It can only cool the transmission fluid to engine coolant temps, ~200F. And fluid temps can rise quite rapidly. I've been actively monitoring the fluid temps while driving, and I don't like what I'm seeing.

I'm going fluid to ambient air. If I find I need a fan I'll add one, but I suspect it won't be required.

I am targeting 150F-165F operating temps. I have been monitoring my trnamsission behavior and coreelating that behavior with the fluid temps for the last several months beginning last summer, and I find it performs best at those temps.

We'll see how it goes
 

harringtondav

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I'm preparing to attempt to install a transmission cooler on my 2020 Ranger. Ford does say to measure at 206F-215F to get the correct fill, but I think thos temps are far too hot, and shorten fluid and transmission life. GM has a sister transmission to the 10R80, and they run it at 150F-165F. Basically 90% the same as the 10R80.

Before I get push back on this, Ford also says you don't need to change the fluid for the life of the transmission... and I don't beleive that either. Here is what came out of my trnsmission at 18K miles (and I babied it). Black as coal!

DSCF0170.webp


There are two ways to go about cooling down the transmission. The simplest way is to allow engine coolant to run through the heat exchanger all the time and install a 170F engine thermostat. The engine and transmission with stay in the 180F - 190F range.

There are 3 coolant hoses on the heat exchanger. You simply need to bypass the thermostat and go directly to the heat exhanger. There are 2 coolant hoses going to the heat exchanger. 3 going to the Thermostat controlling the coolant flow to the exchanger.

A = The electrcially controlled thermostat
B= Heat Exchanger

You want to bypass the thermostat entirely. And route the in/out coolant lines from the thermostat down to the heat exchanger. Protect the thermostat ports by installing coolant caps in case you ever want to reverse the change. Keep the thermostat electrically connected to keep from throwing an error code. It will still open and close, but won't do anything, as no coolant will be flowing through it.

The 2 hoses going to the engine are the ones you want to reroute to the heat exchanger. Pick up a brass nipple or two with hose clamps if you wish to use the existing hoses.

It is not difficult, but the area is tight to work in.

10R80 Cooler Image 3 .webp


The 2nd method is more comprehensive and the one I am going with. I'm going to install a transmission cooler behind the front grill and bypass the heat exchanger completely.

You'll need this adapter to replace the heat exchanger.

Trans Adapter 2.webp
Trans Adapter 1.webp


Then run a pair of AN8 PFTE hoses to the cooler.

I expect to see temps staying between 150F - 165F. I really won't know until I complete the project.

I will probably start the work this spring. I have all the parts. Just waiting for slightly warmer weather.

Expect to pay $350 - $500 for the parts and tools to do the job. The adapter along was $100. A good quality cooler will run $150, then it is hose and AN8 fittings.

Routing the hoses and mounting the cooler will be the tricky part. I'll pull the grill to see what kind of room is available, then I'll need to fabricate a bracket to mount it. I want it a couple of inches from the AC Condenser and Radiator.

I don't know if this helps you any, but this is my analysis of the possible options, and my plan.
It will be a challenge with the transmission in the truck. I was considering the same adapter which is used for a true fluid flush while I was installing the PPE pan. The heat exchanger must be removed and the adapter put in its place. I passed on the project. The cooler is wedged in a very tight space. If I had a lift I might have considered it, but on stands it was too much for me.

Something to consider is the heat rejection requirements for the entire truck. When I worked for Deere a major challenge was finding room and location for the radiator, hydraulic/trans cooler, A/C HX, engine oil and charge air coolers. Each design group was fighting for the front position. ...after that the ambient air became hotter.
An ambient air trans HX will reduce fluid temps, but it will raise air temps for the other HXs. Hopefully not too much.
 

Grandaccess

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Its oil not water so 215F is not out of bounds, 215C however! ...
this morning when mine was Cold (around 10F) it slammed 3rd gear so hard I thought I was hit from behind

215F.webp
 

harringtondav

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Its oil not water so 215F is not out of bounds, 215C however! ...
this morning when mine was Cold (around 10F) it slammed 3rd gear so hard I thought I was hit from behind

215F.webp
We just got through a very cold snap. -15F. I also experienced a very hard 2-3 shift. The only shift issue in six years. For the rest of the cold snap I crept up on the acceleration until I got a good 2-3 shift, then all good after.
 

Dr.Doug

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How are you guys monitoring transmission temps?
 
 








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