Most people think the stock "cooler" in the radiator is a cooler, but you will find that a lot of good effcient trannys and converters actually need heat put into the fluid from the that "cooler" shruggy
I would take your radiator to a good shop and have them swap the bottom part to one that has that heater/cooler in it and then run a tranny temp. gauge in the tranny pan to see how hot your fluids get their in the summer before adding any other additional cooling to it twocents
The reason I'm saying and advising that is I had a tranny temp. gauge in my first Cummins powered pick up (1998 24 valve with the OEM tranny) with the factory towing package, that stupid tranny fluid never got above 140 F driving the crap out of it on the high desert on Victor Valley in the summer empty, NOT GOOD tsk
It would get up to around 230 F when towing my 24 Ft Pace Shadow enclosed trailer up the Baker grade(14 to 18 miles straight up it going from 800 Ft. elevation to 4400 ft. at the top) at the top in August after lunch running it up there at 70 MPH locked out of O.D., it would cool down to 160F as soon as I let off to coast down the other side, it would run between 160 and 200 F on the flats towing it between 70 and 85 MPH in the summers going to the races in Las Vegas or Bakersfield shruggy
Most of the additives in all ATF are design to start working at or above 160 F, not cooler tsk

Last edited by Cab_Burge; 10/09/18 07:46 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)