Hendrick signs Johnson through 2015

HOMESTEAD, Fla. -- Jimmie Johnson, on the verge of a NASCAR-record fourth consecutive championship, signed a contract extension Friday to drive for Hendrick Motorsports through the 2015 season.

The announcement comes just two days before Johnson likely will wrap up the Sprint Cup championship at Homestead-Miami Speedway. Johnson goes into Sunday's finale with a 108-point lead over Hendrick teammate Mark Martin and needs only to finish 25th or better to win the title.

"Jimmie is charting new territory in our sport, and that's due to a combination of natural talent and unsurpassed work ethic," team owner Rick Hendrick said. "How he's committed himself is just incredible, and it shows in everything that he does -- not just on the racetrack.

"There's no question that he's one of the great champions in all of sports, and he's not done yet."

Johnson's previous contract expired after the 2010 season. This is his third contract extension since joining Hendrick in 2001.

Home improvement chain Lowe's also signed an extension as primary sponsor of Johnson's No. 48 Chevrolet through the 2013 season.

"So fortunate to have my team, job, situation at Hendrick Motorsports," Johnson said. "Lowe's has been nothing but amazing to Hendrick Motorsports, to myself. The only car I've driven in the Cup Series has been a Chevy. It's been a Hendrick Motorsports Chevrolet and a Lowe's Chevrolet. I'm very, very proud of that stuff."

There was no immediate announcement on crew chief Chad Knaus, who has previously extended his contracts to stay in line with Johnson. But Hendrick said talks have begun with Knaus and they are "in the process of putting it on paper."

Knaus' current contract is through the 2010 season, and he and Johnson have been partnered since Johnson's 2002 rookie year.

"I think our goal and everybody's on the same page, keeping this thing together for the foreseeable future," Hendrick said.

The Johnson extension locks up Hendrick's lineup in the Cup Series for the next several years.

Martin this season agreed to a two-year extension through 2011, Dale Earnhardt Jr. has three years remaining on his contract and Hendrick said four-time series champion Jeff Gordon will drive for several more years.

"As long as I'm healthy and competitive and we have sponsorship, you know, we're out there enjoying ourselves, I'm going to keep doing it," Gordon said. "I don't like to put a number on that. You know, things can happen in a hurry. Right now things are going well."

Information from The Associated Press and ESPN.com's David Newton was used in this report.