Back when they were 120-140$ I would have agreed with you now that they are 180-220 shipped. I would say the $80 30k cooler is just fine for a stock vehicle.

 

I forgot to mention the bigger ford trucks of certain years have stock coolers almost identical to the 40k. About $110 from the dealer.

 

You can still get them for $150 without a bypass if you do some googling.

I dont think you can really run a trans too cold. There used to be a chart on FLTs website with a trans temp to life expectancy comparison. They basically said if you keep it around 120* itll outlast one run at 180* 2:1.

The main reason I would run one is youre bypassing the radiator and loosing all the stock cooling capacity. On my yukon it was very easy to hit 200* with the factory cooler setup (it already had an auxiliary, but the stock one is tiny).

 

^^ This chart?

 

Shipped? I don't think so. Cheapest I have found is a hair over 160 shipped. As for temps you can run too cold. Under 100* will be too cold causing it to be less efficient and putting additional strain on the pump. Just bypassing the radiator cooler will cause a solid drop in trans temp as the internal cooler can actually raise the temp of your trans fluid. It is also fairly prone to failure. In the case of a stock truck that doesn't see more than say 10,000lbs towing, a 30k will work just fine and for about half the price of a 40k. Is a 40k better? Sure in many cases it is, but necessary in many cases no its just not.

 

There is a reason for the factory trans cooler in the radiator. You can pull heat faster with Liquid then you can with air. This usually proves effective when towing . That's why they run it through the radiator first and then through an external cooler.

As far as the 40K's go if your not maxing out your set up you probably don't need one as you discovered. That 30K is probably a much better choice especially for a stock type application.

For Everyone else it's cheaper to buy the 40K cooler with By pass and then sell the by pass if you don't need it. You only save $10-$15 by not getting it, but the By pass is nearly $60 by it self. You could easily sell it for $40-$50

I would be really interested to see what your temps are on a long drive or towing in the summer heat with the 30K set up by it self.

 

My 30K came with a fan on it and I got the T-stat that turns fan on at 180* one off at 160*


Mounted

 

I run the 40K with a stock torque converter and it does run pretty cool when its under 80* ambient..
Im thinking about putting a blocker infront of it so no air can go across 75% of it and see if it does better.. even when towing something, if the TC locks the TFT's drop to the 110-120* range.