spring under axle?

This question is of no real importance other than curiosity, but does any body know why sometimes leaf springs go under an axle and sometimes they are above it. I know the back end of the xj has the springs above the axle while the leafs on comanchees, yj's and cj's go under the axle. is there any benifit to one way or the other. there must be some sort of reason for two different leaf spring methods.

if you search the interweb you can find out more to the answer but generally under axel setups have a softer ride less axel wrap and in some cases better handeling. spring over has better flex and less hanging low to get snagged. Im just generalising and using what I remember from my days at UTI

I would "guess" if you wanted lots of suspension travel and height, like on Pick-Up Truck, you might get better characteristics from putting the spring above the axle (for the height) than you would from putting even more arch into the spring to get the same height from under the axle. Might be why some have the spring above the axle.

Hear say

I don't konw the true reason but I've heard if the leafs are under the ax, it'll give it better clearance for the pumpkin. I just flipped mine (87 mj) from under to over and it gave me 6" with the stress leaf left in....

thanks, this was pretty much what i was looking for just some general info. Your thought about the differential clearence occured to me too, but i realized that the hight the diff is above ground is only based on tire size.