Catholic Super has moved to quell uncertainty surrounding the future of its banking business after it revealed details of a plan to "joint venture" its superannuation operations with Equip Super.The two industry super funds yesterday announced their intention to begin operating under a common board of trustees while also continuing to service each of their memberships through separate brands.The planned merger would create a new superannuation entity with custody over more than A$26 billion of members' assets.According to the latest APRA data, the new organisation would become the 17th largest superannuation provider in Australia behind IOOF and Hostplus.However, the deal has raised questions about the future of Catholic Super's banking subsidiary, which markets competitively priced home loans, term deposits and transaction accounts to its 75,000 members.The banking arm, one of the smallest in Australia, trades under the MyLife MyFinance moniker and has a loan book of around $120 million.MyLife MyFinance is directly owned by Catholic Super and its business case was developed in 2016 by former ANZ and NAB executive, Mark Ellis, to meet the fund's strategic goal of providing ethical banking services to members.Ellis, who is now the chief operating officer at Catholic Super, said he expected the banking arm would remain in the fold of the new superannuation entity."Catholic Super is committed to providing superannuation, advice and banking services to its members," Ellis told Banking Day."It's a different service offering to what Equip Super offers its members."Under the proposed integration plan, Catholic Super can nominate five trustees to the new common board while the larger Equip Super fund will have seven nominees.Ellis conceded that the new board of trustees might decide in the future to outsource the banking function."Who knows what the new trustees will want to do in two or five years' time," he said.However, if that were to happen Catholic Super members might come off second best because its banking arm has consistently undercut ME on home loan pricing for several years.MyLife MyFinance currently offers owner occupier mortgages at the headline and comparison rate of 3.79 per cent.ME's best-priced mortgage is pitched at 3.87 per cent but has a comparison rate of 4.30 per cent.Banking Day understands that both super funds hold small equity parcels in ME.Equip Super's current CEO Nick Vamvakas was previously ME's chief financial officer.