Forum Discussion
LarryJM
Jul 01, 2017Explorer II
Bypassing the OTW cooler in the bottom of the radiator is the worst thing you can do for maintaining tranny temps especially when towing. It it always the first cooler that the hot tranny fluid goes thru since it is the one that can extract the most heat due to the temp differential and is not dependent on the speed of the vehicle like the OTA cooler is. You examples of light weight non towing vehicles and any comparison of turbo intercoolers is comparing apples to oranges and IMO your worries about cooler failures is basically not founded on any data or reliable reports I have ever read.
Even the gaggle of engineers at FORD failed to appreciate this in the original design of the SD series when all they initially had was the OTA cooler and started loosing trannys from heat especially for those who were towing. They had to put out a service bulletin to replace or add the OTW cooler in the bottom of the radiator to solve the issue.
My recommendation is not to MUCK around with the engineered design of your OEM cooling system and definitely DO NOT bypass that OTW cooler in the bottom of the radiator if you want to keep your tranny.
Larry
Even the gaggle of engineers at FORD failed to appreciate this in the original design of the SD series when all they initially had was the OTA cooler and started loosing trannys from heat especially for those who were towing. They had to put out a service bulletin to replace or add the OTW cooler in the bottom of the radiator to solve the issue.
My recommendation is not to MUCK around with the engineered design of your OEM cooling system and definitely DO NOT bypass that OTW cooler in the bottom of the radiator if you want to keep your tranny.
Larry
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