* Front Axle: A solid front axle, usually a Dana 44 or a less common Dana 50 (depending on options and trim level). This is a heavy-duty axle designed for off-road capability.
* Rear Axle: Most likely a Chrysler 9.25" or, less frequently, a Chrysler 8.25" (again, depending on the options and trim level). The 9.25" is stronger and more common in 4x4 models.
It's important to note that without knowing the specific options and trim level of the 1990 Ramcharger, this is just a general answer. To be absolutely certain, you'd need to check the vehicle's documentation (owner's manual, build sheet, etc.) or look at the axle itself for markings identifying the manufacturer and model.
