Hedge fund lenders to Delphi, the car parts maker with close links to General Motors, are seeking to throw a wrench into the two bankrupt companies’ restructuring plans by objecting to an allegedly secretive deal under which Delphi plans to sell its assets to GM and California-based Platinum Equity.

The funds, including Double Black Diamond Offshore and Greywolf Capital, alleged in a court filing that the sale failed to maximise the value of Delphi’s assets pledged as collateral for their loans.