Grey Power is studying a proposal to take the pension away from retired people who earn more than $80,000 a year.
The proposal is being sent out as a "discussion paper" and has already raised fury within the organisation.
It has also invited Retirement Commissioner Diana Crossan to speak to its ruling board before the end of the year.
The lobby group's dalliance with the "sacred cow" of New Zealand politics has already sparked anger in some sectors and prompted a renewed pledge from Prime Minister John Key to resign if superannuation was changed under his government.
The proposal, leaked to the Herald on Sunday, was written by Grey Power's Coromandel representative, Mac Welch, and distributed by the organisation's president, Roy Reid.