Josh Frydenberg nominated busting the grip of unions over Australia's $1.9 trillion superannuation industry and giving a leg up to retail super funds as one of his first priorities upon becoming Assistant Treasurer.

But the star recruit of Prime Minister Tony Abbott's recent cabinet reshuffle has not exactly put his own hard-earned money where his mouth is on creating a level playing field for commercial and industry super.

'Safety concerns' :Assistant Treasurer Josh Frydenberg Credit:Eddie Jim

An update to Mr Frydenberg's pecuniary interests register shows the Kooyong MP has switched his work super out of an AMP super fund (retail) into Australian Super (industry).

He retains a super account with Mercer (retail), according to the register.