Kasey Kahne, the popular 18-time NASCAR Cup Series winner who’s been with the sport since 2004, just announced his retirement, saying racing has taken its toll on his life.

“The highs didn’t outweigh the lows and the grueling schedule takes a toll on your quality of life,” Kahne says in a he posted to Twitter announcing his retirement.

The 2004 Sunoco Rookie of the Year goes on to say he wants to spend more time with his son and with his sprint car teams. Here’s his full statement:

Kahne, who to talk with readers in 2011, started his NASCAR career in 2004 and ends in 2018, totaling 15 seasons during which he won 18 NASCAR Cup Series races. This year, he’s driving the No. 95 car for the Leavine Family Racing team, and as he says in the statement, the team still has “some work to do.”