HappiJac recommends applying a coat of good auto wax to the lower legs as routine maintenance. The lower leg of one of mine had quite a bit of peeled paint with some rusty and pitted areas. I sanded it down and gave it a couple coats of gloss black Rustoleum.
My new pair of 4600s are here and I'll put them on tomorrow. Bit of a quality problem with one of them though. The little plastic axle opposite the motor release lever has no head on it and there is a gap between the axle and the hole. I'll have to see if I can get HJ to ship me just that small piece because I sure don't want to ship back the whole jack just for that.
-jj