-- A Senate committee, distressed by the different treatment of Delphi Automotive LLP's salaried and hourly retirees, wants to know how the decisions were made by the Obama administration.

In July, Delphi saddled the Pension Benefit Guaranty Corp. with responsibility for the pension plans of 70,000 Delphi workers and retirees.

That move was estimated to cost the PBGC, the government's pension insurer, about $6.25 billion. Recent estimates put it as high as $6.7 billion.

Under agreements with Delphi's former parent company, General Motors Co., GM is topping off the pensions of United Auto Workers retirees while the 15,000 salaried retirees stand to lose a chunk of their pensions.

"General Motors did the right thing by many tens of thousands of workers under union contracts, and 'topped up' their pensions" -- meaning hourly workers won't lose out, said Committee Chairman Tom Harkin, D-Iowa, Thursday at the committee hearing. But salaried retirees stand to lose some benefits and Harkin plans to question GM about it.

Harkin wants GM to fund the pensions of Delphi salaried retirees, as it did for union retirees. Others in Congress have introduced a bill to provide government health insurance to replace coverage salaried retirees lost.

Delphi's salaried retirees say the average retiree will lose $300,000 in pension payments over a lifetime.

Sen. Mike Enzi, R-Wyo., said the Obama administration's auto task force must answer questions about the deal that left salaried retirees in the lurch.

"This type of deal negotiated behind closed doors out of the public view is exactly the type of deal-making that we have long criticized the PBGC for undertaking in years past," Enzi said.

"Everyone needs to know and understand what promises were made, who negotiated this deal and how this administration also prepackaged the GM bankruptcy arrangement."

Delphi exited four years in bankruptcy court this year, with more than $2.5 billion in financial support from GM funded through government loans.

Enzi vowed to write Treasury Secretary Tim Geithner, seeking all records on Delphi's pensions.

Sen. Sherrod Brown, D-Ohio, said many Delphi retirees are facing "drastic reductions" in pension benefits. He said Delphi cut off health and life insurance to salaried retirees this year.

"They simply are not being treated fairly," Brown said.

Rep. Tim Ryan, D-Ohio, said Delphi forced many younger salaried employees to retiree early, then terminated their pensions and canceled their health care benefits. His district in northeast Ohio has 5,000 Delphi retirees, and the loss of income is "devastating," he said.

Bruce Gump, a Delphi salaried retiree, told the committee that some retirees would lose up to 70 percent of their pensions, and many would be left "at or even below the edge of poverty," he said. "No other group in the auto industry faces this."Salaried retirees at GM and Chrysler Group LLC lost nothing in pensions, despite the bankruptcies at those companies, Gump noted.