Holy Crap, someone that gets it! :thumbIFS is a superior design except for one area, the potential for wheel travel, and this only comes into account in extreme off road. Bottom line, it is cheaper to design and install solid axles and (not to be rude in anyway) the lack of understanding that solid axles are stronger.
Think about this, all Toyota's, Ram, and ford 1/2 tons all brag about IFS on their trucks Ford even puts IRS?? (independent rear suspension) on their large SUV's (which I don't get). If solid axles are so great why don't they still use them on all of those vehicles? Ford is that last hold out on solid rear axels in the mustang ... would imagine that they would see the light and install IRS on it soon.
I have always wondered why GM puts IFS in their 3/4 tons and 1 tons. Dodge and Ford all have solid front and rear axles. So is there something that GM knows that they do not?