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I believe Ford offered the transmission OTW cooler via a modification for the 2000 MY that didn't initially come with it when the later models came out with it from the factory. That is most definitely not the case anymore, but I am fairly certain that part of history has been said here before, but I could not find the source...
Does DieselSite recommend running multiple coolers in line if the OTW radiator cooler is still installed? YES
Do they recommend removing the OTW radiator cooler from the plumbing of their 4R100 cooling system? NO. Never under any circumstances
I am behind due to life crazyness.
Broke by OTW are you referring to the trans cooler lines being routed into radiator prior to cooler?
Yup, thats the one.
***off topic
About 6 years ago I built a Ford F700 that had a giant Allison Automatic (MT643). In order to cool that beast it needed some big coolers. For the OTW I used a cooler that was intended for boats that mounted separate from the radiator. Big tube looking piece with coolant hoses on either end and transmission lines in the top. IIRC the MT643 runs 1" lines. From there it went to a GIANT Hayden Oil-Air cooler behind the grill. Giant as in 18" wide by approx. 30inches tall. Wanted more capacity so from the cooler I routed it into a modified Canton 3gal dry sump oil reservoir. The finally back into a deep sump pan. IIRC the system holds somewhere around 8 gallons of fluid and I run Coastal Premium Hydraulic Oil (Hygard rated). Allison rates their systems (out of the torque converter) at 300* MAX. Cooled great and would at times get a little warm, but at approx. 380hp grossing over 36k its expected. It could pull the majority of the big grades on I-75 through KY, TN, GA without losing any speed.
My e99 doesnt have the radiator cooler option from factory.
So mine is just the mishi cooler.
My main belief is that the otw helps warm up and keep trans temp reasonable in cold weather.
I know my tuning runs my converter unlocked on cold start ups until the trans is aproxamatly 80°
It seems to work decent, but then again the truck hasnt been driven in winter until this year,and now it is down for unkown amount of time, so it may miss yet another winter.
My e99 doesnt have the radiator cooler option from factory.
So mine is just the mishi cooler.
My main belief is that the otw helps warm up and keep trans temp reasonable in cold weather.
I know my tuning runs my converter unlocked on cold start ups until the trans is aproxamatly 80°
It seems to work decent, but then again the truck hasnt been driven in winter until this year,and now it is down for unkown amount of time, so it may miss yet another winter.
Mark K often states the OTW cooler NEVER heats the ATF. The top of the radiator has ~190* coolant temps but by the time it reaches the bottom of the radiator by the OTW cooler it is "near" ambient temperature. I believe this large temp difference between the top of the radiator and the bottom is often overlooked leading people to believe the ATF in the OTW is being cooled by 190* coolant. That is just not the case. Get the truck to running temp and get under and grab the lower radiator hose and you can feel the difference.
Mark K often states the OTW cooler NEVER heats the ATF. The top of the radiator has ~190* coolant temps but by the time it reaches the bottom of the radiator by the OTW cooler it is "near" ambient temperature. I believe this large temp difference between the top of the radiator and the bottom is often overlooked leading people to believe the ATF in the OTW is being cooled by 190* coolant. That is just not the case. Get the truck to running temp and get under and grab the lower radiator hose and you can feel the difference.