DETROIT - The cash for clunkers stimulus program helped the auto industry but there is no need for another similar program, General Motors GM.UL Vice Chairman Bob Lutz said on CNBC on Monday.

I think it was good the first time around, Lutz said. I don't think it's a program you run and run and run and run.

Lutz said the U.S. government's $3 billion program to pay up to $4,500 to new car buyers if they traded in an old car that met program specifications brought atypical buyers into the market.

Boosted by cash for clunkers, U.S. auto sales in August reached a 20-month high, leaving some analysts to wonder if September sales will take a nosedive without the incentive program.

As most dealers will tell you these were not your normal, used car buyers, Lutz said. So, (cash for clunkers) genuinely did provide a stimulus and got a bunch of old and heavily polluting vehicles off the road.

Lutz on Monday was making media rounds to pitch a 60-day, money-back guarantee on new vehicles that GM and Lutz announced last Thursday. It is accompanied by ads that will feature GM Chairman Ed Whitacre telling consumers that GM's cars are much better than the public's opinion of them.

Lutz, 77, seven months ago said he would retire by the end of 2009, but in July said he had reconsidered and would not retire.

He said he changed his mind in large part because the new 13-member board of directors of GM, which is owned 61 percent by the U.S. Treasury, is allowing the company to act like any other company without major interference. (Reporting by Bernie Woodall, editing by Dave Zimmerman)