The $2.3 billion ANZ Australian Staff Superannuation Scheme has overhauled its Australian and international equities portfolios to include the appointment of two new core managers and four satellite managers.

According to an investment update on the corporate super fund's website, the fund's Trustee has restructured its international and Australian equities portfolios to cut costs and level the amount of its risk exposure.

ANZ Staff Super axed its mandates to WestLB and BGI to manage Australian shares. Russell Investment Management's mandate to manage the Australian and international shares portfolios have also been canned. However Russell remains an international shares satellite manager to look after the scheme's emerging market share exposure.

Meanwhile Macquarie Investment Management has been appointed the core manager of the fund's Australian shares portfolio, with 70 per cent of the allocation now invested in the Macquarie Pure Index Fund.

Barclays Global Investors has snagged the international shares core mandate. Around 70 per cent of the portfolio will be invested in the BGI Fission Index Fund.

ANZ Super Fund's new satellite managers for international shares include Altrinsic Global Advisors and Trilogy Global Advisors. For Australian equities, London-based Orbis Investment Management Australia P/L, and boutique manager Independent Asset Management P/L have been appointed satellite managers.

Both core managers will adopt a passive investment style, with the aim of matching or exceeding marginally the investment performance of the Australian and international share markets respectively.

At the other end of the spectrum, the satellite managers will execute an "active" style to outperform their respective markets.

"The new approach is designed to improve investment returns whilst reducing the costs associated with these investments and maintaining the same level of risk in the market," the fund said in a statement.

"It is envisaged that investment costs will fall by about 40 per cent from current levels for the aggressive and balanced investment options," it said.

The fund's changes are expected to be finalised by September.