For my money,it's better to replace the whole rear end.Usually just a matter of changing the spring pads,and sometimes building a set of shock brackets. (and bleeding brakes,again.)
I have a 3.08 in my GMC;it's theoretically good for something like 129 at 4,000 rpm. Of course,it takes a lot more horsepower than I have to push a barn door up to 129 mph. I run about 1500 rpm at 60 mph.(Thanks to the LT235/85-16's)
I guess taller gearing is better-you can always downshift if you run out of power,but what can you do if you run out of rpm?
James
