Kreyer began racing in half scale NASCAR cars in the Junior Cup series in 1995. He won four straight championships in 1995 to 1998. He competed in the series part-time in the 1999 season while working on the pit crew for NASCAR Midwest Series driver Jason Schuler.

Kreyer competed full-time at Wisconsin Dells in 2001, finishing third in the final points. He also competed part-time in the Wisconsin Challenge Series that season. Kreyer competed at several tracks in Wisconsin in 2002.

In 2003, Kreyer competed at full-time in the Wisconsin Challenge Series, and at Wisconsin Dells. He finished fourth at both the track and the roaming series. Kreyer competed in the Wisconsin Challenge Series and CRA Super Series in 2004.

He competed in half of the American Speed Association late model races in 2006, but he was able to score enough points to finish in the Top 20 in points. Kreyer purchased Wisconsin Dells Speedway with two other co-owners, closing on the purchase of the track in February 2007, and renamed the track Dells Raceway Park. The new owners have brought the American Speed Association sanction to the track.

Kreyer made his first NASCAR start in the Craftsman Truck Series at the Kroger 250 at Martinsville Speedway on March 31, 2007. He started 27th and finished 28th seven laps behind the leader. He also started 22nd at Mansfield Motorsports Speedway, and finished 34th with motor problems.

He started two Busch series races in 2007. He started 32nd and crashed out finishing 34th in his home race at the Milwaukee Mile. He started 38th at Gateway International Raceway, and finished 38th with brake problems.

Early in 2007 Kreyer announced that he would be attempting to qualify the Mac Hill Motorsports car for four NASCAR Busch Series races in 2007. He made all four races and had a best finish of 28th at O’Reilly Raceway Park.