Well, there are a lot of variables to answer that question.
Lower gear ratio's like 3.91, 4.10, 4.88 are going to give you a lot of bottom end power but will limit your top end speeds.
Higher gear ratio's like 2.73, 3.23 will give higher top end speeds but will take a lot of power away for towing, hauling heavy loads, etc.
Also, tire sizes should be figured into the decision along with the type of engine.
Big blocks and poly small blocks can handle a little high ratios than 6's and LA small block which need more gearing to overcome the lack of torque and horsepower.

So, you pretty much have to decide what will best fit your driving needs.

Mark D.

1968 W200 Sweptline
1969 D100 Utiline
1971 D100 SE Sweptline
1993 D250 Club Cab Sweptline
1986 W250 Cab & Chassis
1978 D300 Sweptline

E. Brookfield, Massachusetts