During the 2000 season, Leffler drove full time for the #18 MBNA sponsored Busch team. He finished 20th in the championship and earned 3 pole positions during the year and finished 2nd at Phoenix. He also made 2 IRL starts, among them a start for Roger Penske in the Indianapolis 500 where he started and finished 17th.
His rookie season caught the attention of Chip Ganassi Racing, who hired the young Leffler to drive his #01 Dodge Interprid in Winston Cup, which was sponsored by Cingular Wireless. During his inaugural Cup season, he won the pole at the inaugural race at Kansas Speedway However, he had only 1 top 10 finish and 4 failures to qualify. After his 37th place finish in the championship, Ganassi replaced him with Jimmy Spencer for the 2002 season.
Leffler joined Ultra Motorsports in 2002 and had great success early on with the team. In his first year, he tied a single season Craftsman Truck Series record by scoring 8 pole positions, and qualified no worse than 8th at any race during the season. Despite not winning a race, 6 second place finishes and a 4th place finish in the championship. Leffler finally broke through in 2003 when he scored his first career victory at Dover. Despite being in the top 10 in points, however, he was fired from Ultra Motorsports ride after taking over in the Haas CNC Racing #0 NetZero Pontiac, which breached his contract with the Dodge-powered truck team.
No speeding in the Park. Bicycles are allowed on all two tracked trails. Do not bike on single tracked trails. Wheels yield to feet, (Hikers and horses). Hikers yield to horses.
Cache placement approved by Martin Morse, Park Service Specialist. Obey all speed limits. Do not block gates. All wheels off the pavement.