[onewhippedpuppy]

There have been a few over the years, particularly higher trim levels. My Ram Limited has a 4wd Auto feature where it automatically proportions power depending on the conditions, much like an AWD system. I suspect it’s more of an “on/off” than actively adjusting power to the front wheels.

Traditional 4wd uses a transfer case and sends the same power front and rear to maximize traction. It’s really only intended for adverse conditions and typically more mechanically robust. AWD typically works through some variety of viscous center differential that automatically proportions power front and rear. It’s a similar concept but less robust and better suited for on road use.