Most of the post sound all to complicated for me. So far I have not found a 6-7% grade that I can't pull in 3rd at not less than 48 mph turning about 2700 rpm. I push my button to drop out of o/d to 3rd and lock up t/c again and go. That's all I have needed so far from my '04.5 Dodge/Cummins. Personally I can't afford an exhaust brake add on or a newer truck at this time so I drive within limits of what I own and it has worked very well in our travel all across the northern part of this fine country. JME.