All 4X4's always use same gearing for front and rear differentials.
Otherwise the transfer case, trans, drive line and both differentials will bind up to the point of breaking from becoming stressed by increasing tension buildup against one another as you continue to drive on hard or soft surface. On hard surfaces (asphalt, cement, etc.) the front and rear drivetrain, even with same gearing, don't turn at the exact same ratio. Thus, the binding of the front against the rear drive assembly's occur due to good traction with virtually no tire to surface slippage.
On the other hand, surfaces that allow tire slippage such as sand, mud, dirt, wet surface, ice, etc. the front/rear tires will slip on the grounds surface due to tension buildup and relieve binding stress as your tires are rolling across it.
If your just pulling a boat from the water on a hard surface ramp, or going a similar short distance using 4 wheel drive, that's not considered being stressful on the drivetrain assembly. But while traveling on hard non slippery surfaces for other than similar short negligible distances, it's advised to not use 4 wheel drive because eventually the drivetrain will wear down to the point of breaking. Guaranteed!
