anyone know of a self leveler that nail down can be installed over?

After I grind the high spots I use thick tar paper, like roll roofing or three tab shingles, for up to a quarter inch thickness. Then if more is needed tar paper and plywood. I use sub-floor adhesive to make sure the ply is secured.

thanks for the reply but was told by someone about a self leveler so that is what I am trying to find info on

I have not heard of a self-leveling compound that doesn't get too brittle when it hardens, or one that can be nailed through. Small areas are fixable with the tar paper technique. I've built up a porch floor to one and five eighths inch at the thick end, over 6 feet with tar paper and plywood.

SLC's compressive strength is at or higher than concrete so I wouldn't advise trying to nail into it.