I had to think about this for a minute, because though it seems possible to freeze spud salad, I'm not sure I've ever seen it done -- and there's got to be a reason for that. Mayo may not survive the freezing process very well.
Why don't you try it though? The worse that can happen is that you'll have to dump it, which you would otherwise have to do anyway.
"Don't you ever underestimate the power of a female." Bootsy Collins