Just to keep the new questions to a minimum. ALL Ramchargers and Traildusters came with a Dana 44 front axle from the factory. If yours has something else, it was done after it left the factory. Usually there is a number 44 stamped in the webbing to the left lower side of the pumpkin. I have never seen one that didn't have it but I guess there may be some out there without it.
As far as the back axle goes, if it is a 70's model, it may have one of three in it, an 8 1/4, an 8 3/4 or a 9 1/4. The 8 1/4 has a roundish cover on the back side and would be fairly rare in a 4x4 but could, and has, been found there. It is more common in 2wd's. The 8 3/4 does not have a cover on it. The ring and pinion are removed through the front like a Ford 9 inch. Much more common in 4x4's and 2wd's. The 9 1/4 has a stop sign shaped (octagon) cover on it and is, by far, the most common rear diff in 4x4's of all years. It is also the only one I know of in 4x4 RC's from 81 to the end of production.
Trucks are another story all together unless you are talking 1/2 tons. The 1/2 tons (D/W 100 and 150's) are basically the same on axles as the RC's. 3/4 tons (D/W 200 and 250's) usually have a Dana 44HD up front but may have a Dana 60. In the back they will have a Dana 60. 1 ton's (D/W 300 and 350's) will be a Dana 60 up front and either a Dana 60 or 70 in the rear. A lot of this depends on engine and other possible options, especially on the 3/4 and 1 tons.
Now, haveing typed all this, someone will start disputing it because I missed some obscure model in there somewhere. This is intended as a general guide not a bible.