Looking to add a tranny cooler to help with temperatures while towing. Does anyone have an idea on sizes to get to supplement the stock one in the rad? I know the tow package has an external one in front of the a/c condenser, but can't seem to find any info on how many BTU's it's rated for. I am looking at either a B&M 70268 that has 13,000Btu's http://www.bmracing.com/PRODUCTS/Aut...U-11x7-1-2x3-4
or the 70266 that has 20,500 btu's of cooling http://www.bmracing.com/PRODUCTS/Uni...BTU-11x8x1-1-2

The reason I am looking at the B&M is it is better for low amient temperatures like Canada in the winter time yet still gives very efficient cooling for the hot weather.

 

i put on on my truck when i first got it but can't remember the brand right now but the reason why i bought it it had a feature that if it was too cold and the fluid was thick it had like a bypass so it wouldn't restrict the flow. something to look at also for cold weather climates.

 

Yes, it's called a "low pressure drop" cooler like the B&M. When it is cold the fluid is thicker and you don't want your cooler to cool it even more, so these things bypass the cooler internally somehow to prevent that.

 

I mounted the tranny cooler last night, tonight I am going to cut the lines and hook everything up. I just want to make sure that I cut the proper line. I need to cut the return line to the tranny, so if what I have found out is right, I need to cut the left hand line (drivers side). Is that correct? Thanks.

 

I don't know about others, but I installed my cooler before the one in the radiator, not after. My thought is that the one in the radiator is really controlled by the radiator thermostat. By putting it before that one it won't overcool the oil in cool weather because the one in the radiator will heat it back up if necessary. In hot weather it will act like a pre-cooler to lighten the work load on the one in the radiator. The end result is that the oil temp is more stable but the system has more heat rejection capacity when needed.

I cut into the line going to the right/passenger side of the factory cooler in the radiator.