I run about 125 so that is close. When does the bypass even open to let the fluid flow what temp?

 

or instead of adding another cooler, just replace your stock one with a 6.0 cooler or a transcool cooler as mentioned above... it will lower your temps, but not too far. I did this on my truck when I replaced the transmission... never saw over 170* beating on it... until it broke. but it wasn't due to heat.

 

its pretty decent sized, not too big though, i love mine, it does what its needed to do

 

The bypass has nothing to do with temp, it is for pressure, incase you had a cooler that got plugged up or something along those lines.

 

I see. Well I am just gonna leave mine its a bit cool so no going back now already installed.