Originally Posted by OldCoot
For the few times you run into a head wind, I doubt it would be worth the time, money and effort. I have a 05 Silverado with a 5.3 and the 3.23 gears and a 5er and just use 3rd gear at 2400 rpm at 55-60mph. If it goes over 60, it will shift into 4th and drop to 1800 rpm. Slight hills will immediately cause it to downshift to 3rd, but maintain 55-60 which is plenty fast enough for me. Trailer tires are only good for 65 anyway. Going in the mountains, I limit it to 3500 rpm regardless of the speed.
This is exactly what I do. I have pulled this TT 8000+miles. It won't stay in 4th gear so to keep it from jumping in and out I keep it in 3rd and my comfortable speed is same as yours. Going through the mountain's of TN & KY if I'm not careful it will shift down and jump to 4500rpms, so I manually pull it into #2 on the shift lever and hold it at 3000rpms. You don't think that 3500 is too high for that 285hp engine?