I own a '62 IH C-20 4x4 (3 sp, 304, 97K miles). It is in pretty good shape, but it's geared like a D9 CAT. Top speed is around 55 MPH and at that it sounds like a jet airliner trying to take off. I want to tame it down a bit and get the vehicle to be more of a daily/weekly driver. I was born the same year as this truck so a quieter, smoother drive is more my speed.
I need some advice: Do I need to change the gears in both the trans and the rear differential? Can I leave the front differential alone since I would only use it on rare occasion (like cutting firewood, or the freak snowstorm)?
Thanks in advance.