I think you may be confusing gear ratio (3.73 and 4.30) with something else. The gear ratio is a numerical value that describes how many times the driveshaft must turn to accomplish one revolution of the (rear) wheels. Nothing to do with ride quality. The rear axle/gear ratio is a bit meaningless unless the overall drive ratio is taken into account.
Generally speaking, the higher the number, the more wheel torque will be applied if the transmission is in a 1:1 gear.
Here's an example:
Tundra transmission ratios:
Gear Ratios
1st 3.33
2nd 1.96
3rd 1.35
4th 1.00
5th 0.73
6th 0.59
Differential Ratio 4.30
So, let's assume for this example there is no artificial (computer limited) torque reduction, and no slippage in the transmission.
In 1st gear, the Toyota Tundra transmission has a 3.33:1 ratio, then on to a 4.30 ratio in the rear axle. This means that at when the engine is putting out say 200 lbs-ft of torque at the engine at a lowish RPM, that is then multiplied by 3.33 and then that is multiplied by 4.30. Engine torque output will increase with RPM (to a point where it peaks).
200 x 3.33 x 4.30 = 2863 lbs-ft.
That will get the load moving, then, as you progress through the gears in the transmission, the amount of torque available at the wheels decreases. This is why the transmission "down shifts" and engine revs increase when load increases (towing up a hill for example).
Gear ratios have nothing to do with ride comfort, that is suspension. Locking differential just means the two rear wheels will both have equal power in low traction situations.
