It depends on the year and tranny if they are different axle ratios. But if you are using the same tranny and just swapping tailshaft for the transfer case, then it doesn't matter as the speedo gear still matches the rear axle ratio. If you are trying to get more lift on the front end by cranking up the torsions and pulling the front diff and axles to cut weight for a prerunner look, it won't be enough of a difference for the work involved.