Northwest Airlines Corp.'s secondary stock offering could put about $170 million into its employees' retirement accounts or pockets. Northwest will set up voice-response phone lines during the next two weeks that employees can use to indicate how many shares they want to sell. Workers can take the money as a lump sum (after taking a tax penalty), or roll it over into an IRA or into the plan's money market account, said an investment banker familiar with the deal. Also, the ESOP plans to add more investment options by next June. Northwest filed a registration statement yesterday for a secondary offering of 8.4 million shares of class A common stock, half owned by Bankers Trust and half by the Northwest Airlines Corporation Employee Stock Plan, which was set up in exchange for wage concessions to help the airline stave off bankruptcy in 1992. At yesterday's closing stock price of $40.50 per share, the employees' 4.2 million shares would bring in $170 million. Board members of the $250 million Oklahoma Law Enforcement Retirement System, Oklahoma City, have asked the fund's consultant DeMarche Associates to further analyze TCW Group. The board will discuss the fund's TCW portfolio at its Nov. 16 meeting. The board met with TCW last week to discuss its performance since being hired in September 1993 to manage a $25 million bond portfolio. A spokesman for the fund, however, said recent performance has been good; he said TCW is up 14.4% year to date, compared with 13.62% for the Salomon Broad Bond index. SunAmerica Asset Management is seeking to fill a new position head of fixed income. Korn Ferry is assisting. The person chosen will oversee the firm's $1.4 billion in bond and money market mutual fund assets. Currently, CIO Stan Feeley oversees both fixed-income and equity mutual funds, according to Peter Harbeck, president. The firm also might add additional analysts and portfolio managers. Lehman Brothers Inc.'s latest move to trim costs by dismissing 300 employees won't hit its asset management business further, a company spokesman said. Earlier this year, Lehman decided to focus its asset management in three areas cash management, performance-based funds in which Lehman invests alongside investors, and managed futures. To concentrate on these areas, Lehman chose to exit other asset management areas, including offshore mutual funds. In doing so, it already has reduced its number of employees. PPM America, a money manager owned by Prudential, plans to file a class-action suit this week against Texas-New Mexico Power for redeeming part of a high-yielding bond issue before maturity, said F. John Stark, senior vice president, counsel and a PPM portfolio manager. PPM will ask the court to rescind the redemption, contending it violated the indenture agreement stating when redemptions are allowed, he said. In addition, PPM plans to send the company a notice of default on its bonds. PPM redeemed its bonds in the redemption, he said. In a rare move by a bond issuer, Texas New Mexico initially sued PPM to head off the money manager from trying to block the redemption.