STEVEN Rattner, the auto industry adviser to Treasury Secretary Timothy Geithner, is flagrantly thumbing his nose at President Obama's call for Americans to make sacrifices in the collapsing economy. Rattner is moving full-speed ahead with construction of a lavish, $15 million summer home in the Lambert's Cove area of West Tisbury on Martha's Vineyard -- a palatial mansion he's had in the works since 2006. It's caused a furor among wealthy Vineyard residents, who've called the planned 15,500-square-foot project far too big and gaudy, The Post's Mark DeCambre reports. Nonetheless, the town's Land Use Planning Committee greenlighted the scheme, which involves transporting an existing building to an adjoining larger property on Obed Daggett Road. Adding to the controversy, the mansion is close to a sacred Native American burial ground protected by a permanent preservation restriction, according to the Martha's Vineyard Times. Rattner has been tough on banks and hedge-fund managers unwilling to take haircuts on stakes they own in failing car companies. Yet Rattner, his wife, Maureen White, the former national finance chair for the Democratic Party, and their four children enjoy plush lifestyles because of the success of his Quadrangle Group hedge fund, which manages Mayor Bloomberg's $16 billion fortune. His fund has been under scrutiny in a pension scandal being probed by state Attorney General Andrew Cuomo. Rattner, 56, who earned more than $100 million from Quadrangle and lives in a huge apartment on Fifth Avenue, donated millions to the campaigns of Hillary Clinton, Al Gore and John Kerry. But when it became apparent that Obama's presidential run had legs, he hitched his wagon to him. A representative for Rattner in Washington had no comment.