whats to small? tranny cooler

[chrisb]

i need to put a tranny cooler on my runner , and i happen to have a hayden 15000btu 1404 fin and tube as well as a tru-cool lpd 12000btu cooler
the tru cool looks a little small but is for sure the nicer higher end cooler do you guys think it will do the trick ,i live in a desert climate so it's hot as hell all the time ?
i've read the tube and fin design is bad because there is no bypass ? is it true or just a internet "dead puppies story"

 

[slides]

I have a b&m 13,000btu and I feel I should have gotten a bigger one due to temps hitting 170 in traffic. I also have it mounted in front of my fan.

Use the 15,000 but

 

[Jaketino]

Use the 15000 btu one. I "borrowed" one from my dad that he thought about using on his jeep that was 21000 btu. On cold mornings it takes the rig forever to warm up.