L. C. Greenwood, a 6-foot-6 blend of power, speed and style who as a member of the Pittsburgh Steelers’ “Steel Curtain” defense in the 1970s helped lead his team to four Super Bowl victories, died on Sunday in Pittsburgh. He was 67.

The cause was kidney failure, the Allegheny County Medical Examiner’s office said.

Greenwood, who had been skinny in college but bulked up to 245 pounds as a professional, played left defensive end, lining up alongside three players with whom he formed one of the most oppressive defensive lines in the history of the National Football League: “Mean” Joe Greene at left tackle, Ernie Holmes at right tackle and Dwight White at right end.

In technical football terms, they were the front four in a 4-3 defense. But after their repeated success prompted a local radio station to name the group as a whole, they became the Steel Curtain.

Greenwood, a master of the quarterback sack, was known for balancing a freewheeling playing style with a remarkable ability to avoid injury. Flying off the left edge, he might not have been as famous as the man rushing in beside him — Greene was the only member of the foursome elected to the Pro Football Hall of Fame — but he was no less fierce or feared.

In 170 games over 13 seasons, from 1969 through 1981, he recorded 73 ½ sacks. In six seasons, he led the team in sacks. (The numbers are unofficial because the N.F.L. did not begin tracking sack totals until 1982.)

Greenwood, who was named first-team All-Pro in 1974 and 1975 and played in six Pro Bowls, also had a knack for knowing where the ball was. He recovered 14 fumbles in his career, including five in the 1971 season, the second most in the league, and he often sprang up to block passes.

In Super Bowl IX in 1975, Greenwood deflected three passes by the Minnesota Vikings’ Fran Tarkenton as Pittsburgh won its first Super Bowl title, at Tulane Stadium in New Orleans. In Super Bowl X, at the Orange Bowl in Miami, he sacked Roger Staubach of the Dallas Cowboys three times in the Steelers’ win. Three years later, in Super Bowl XIII, again at the Orange Bowl, he sacked Staubach once more in another Steelers victory.

His flair as a player extended to his footwear. After he sustained an ankle injury in the 1973 season, a Steelers trainer insisted that he would have to wear high-top cleats to play in an upcoming game. The trainer, Tony Parisi, proposed black or white cleats. When Greenwood rejected both, he proposed painting a pair gold. (The Steelers’ colors are black and gold.) Greenwood wore the gold cleats for the next two games, both of which the Steelers won, and he eventually began wearing the gold high-tops for games even after his ankle healed.

The oldest of nine children, L. C. Henderson Greenwood was born Sept. 8, 1946, in Canton, Miss. In “About Three Bricks Shy of a Load,” Roy Blount’s book about the Steelers’ 1973 season, Blount wrote that Greenwood initially told him that L. C. stood for “Lover Cool” but later insisted that the letters did not stand for anything.

Greenwood was drafted in 1969 in the 10th round from Arkansas AM&N University, now known as the University of Arkansas at Pine Bluff. It was the first draft class selected under the renowned Steelers coach Chuck Noll.

Greenwood became the starter at left defensive end in his third season, 1971.

After his playing career, Greenwood went into business, starting several companies in coal, construction, engineering and packaging.

The Steelers’ Web site said his survivors include his children, Chelsea and Fernando Greenwood; his sisters Shelly Greenwood, Annie Greenwood, Goffan Greenwood Simmons, Katie Greenwood Young and Janice Greenwood Aderhold; his brothers Moses Jr., Henry and Michael Greenwood; and two grandchildren.

Of his Steel Curtain teammates, only Greene survives. Holmes died in a car crash at 59 in January 2008, and White died at 58 the same year, in June, from complications after back surgery.

One of Greenwood’s nicknames in his playing days was Hollywood Bags, a reference to his often-expressed desire to go into acting after his football career ended. Greenwood eventually joined the Screen Actors Guild and other acting organizations, and he appeared in several commercials, most notably one in 1984 in which he offers to buy Miller Lite beers for quarterbacks he has “crushed” in the past.

“Dear Quarterback,” he says, wearing a Cheshire cat smile as he reads aloud from a letter, “I apologize for the way I treated you.”