NEW YORK (Reuters) - Washington Mutual, the giant bank and home lender slammed by the mortgage slump, said on Monday it would strip Chief Executive Kerry Killinger of his title of chairman starting next month.

The Seattle-based savings & loan said independent director Stephen Frank will become chairman of the board on July 1. Killinger, who has presided over WaMu's plunging stock price and earnings, will remain CEO.

Frank, 66, has been a director since 1997 and is the retired CEO of utility company Southern California Edison.

WaMu said in April it would consider splitting CEO and chairman roles at a future board meeting. Angry shareholders have agitated for management changes following the bank's weak performance.

In another result of shareholder lobbying, the board adopted a majority voting standard. In uncontested director elections, nominees must receive a majority of votes cast to be reelected.

WaMu, whose board has come under fire, also changed the leadership of key committees and is searching for new independent directors with backgrounds in finance.