I was fully confident (still am) in driving my 216 w/4:11 gears round trip from TN to Prudhoe Bay, AK for the cancer drive (see link in sig.) until a very generous soul donated the 3:55 set from Patricks back in 2000. The trip was 11,802 miles and eight weeks with only a generator rebuild, broken muffler bracket, and some flat tires. The next summer we drove the entire Route 66, no problems.
Don't think for a minute it couldn't have been done just as well with 4:11 gears. I drove many years and thousands of miles with the 4:11 and part of my inspiration for doing those drives was to prove it could be done with a stock AD truck. Takes patience and careful route selection, but when it comes down to it, miles is miles.
One day after returning from AK I went to a truck show 640 miles from home in Jenks, OK. I did the return trip in one day during a 104 degree heat wave. Left Jenks at 6:00 am and got home about 9:00 pm. I was exhausted, but man what a feeling of accomplishment!
To do that kind of driving in a stock truck successfully it's all about route selection and giving yourself lots of time. If you're in a hurry, drive a modern car.
