[RMcNeal]

I think he means that since they are so much higher off the ground, it is less likely that rain will splash sand and dirt up on the exposed ram. I use blocks made from 4x4's and 2x4's that are about 7 1/2" high and that's why in my case. I raised all of my jacks as high as possible because we have a couple of sites that we frequent with a severe slope to get in and out. Jacks would drag if they were not raised.