Ok so I think I know the answer to my question but i wanted to get your guys opinions.
When I did the motor swap, I upgraded the stock OBS tiny trans cooler with a summit brand tube and fin cooler due to the lower cost vs the Tru-Cool that everyone swears by. I had planned on getting a 21-22' boat in the future when i was doing the swap and I told that to chris at circle D when I was choosing a converter. He said the 2800-3000 stall would still be ok for towing so I got it. temperatures have been fine for 2 years now towing my 3 jet ski trailer around even in 100 degree weather.
Well I finally got my boat last week and went bigger than originally planned. its a 25 footer. Truck weighs 4500 with me in it (empty bed) and the boat/trailer is another 5500-6000 lbs. Took her to the lake on saturday and the stall really makes the 6.0 have to rev up to get going. On flat highway locked up, temp is around 210 (normally 190 without a trailer). But there is a nice long grade that i had to climb and boy did i have to turn the heater on!!! she got up to around 250 (coolant temp)... thats too much for my liking and i started to smell something burning but couldnt tell exactly what it was. I assume it was trans fluid. I have not hooked my trans temp gauge up yet so i dont know what it was at but i know it had to be WAY UP THERE.
So I came to the conclusion that i needed to reduce the stall if i want to help keep temps down. but in doing research, i found that a lot of guys saying they are running a 2800 stall and even higher with no issues.... so that got me a little confused. Then I thought about the cooler and in doing research on that, aparantly the tube and fin type is the least efficient and the tru cool 40K is the stacked plate type which is the most efficient and is designed for heavy towing.
So my question is, am I right in thinking that the stall is not the problem and what i have is fine and all i need to do is get the 40K and be done with it? $150 cooler vs a $3000 trans/verter rebuild is money well spent. I know I took some life off both of them this last trip so i want to get this fixed before the next one (hopefully next sunday)
What do you guys think? re-stall, 40K, or both? or something else im missing? Engine oil cooler worth the dime??