No. Why would they? The only reason some cars utilize different ratios is to allow a continuous, small transfer of torque to one axle when the center coupling is viscous. In a viscous coupling, no torque is transferred until there is some slip. If the ratios are the same, then generally there will be no slip, and the torque goes to one axle (the front). As soon as the front wheels started to spin, torque would suddenly be transferred to the rear as the fluid heats up and thickens. The last thing you want is sudden torque transfer to the rear in a low traction situation. So they "pre-tension" the coupling by having different final drive ratios. It "seems" like the rear is always slipping, so there's almost no "play" in the coupling. Torque transfer under slip conditions is smoother.
In any other diff setup, different final drive ratios will just cause the diff to melt - you'll be constantly fighting the diff's slip-limiting action by causing perpetual "slip".