In 2006 Coulthard signed to drive with Paul Morris Motorsport, he shared a car with Alan Gurr and Steve Ellery. Coulthard returned to drive the older model VZ Commodore for the same team in 2007, before stepping out after Bathurst to concentrate on his 2008 plans.
Coulthard enjoyed a breakout season in 2008 driving for Thief Racing. Driving a Ford BF Falcon, Coulthard finished in the top ten on six separate occasions, including fifth place on home soil in Hamilton, New Zealand and finishing the season in a respectable 13th in the championship. In 2009 he returned with PCR, driving a brand new Ford FG Falcon having another consistent year behind the wheel of the Falcon. At Symmons Plains Raceway Coulthard broke through for his first podium result in V8 Supercars, finishing third at the 2009 Falken Tasmania Challenge and finished the season in another consistent 16th in the championship.
In 2010 he joined Walkinshaw Racing, the same operation as the famous Holden Racing Team. On the first lap of the 2010 Supercheap Auto Bathurst 1000, his left-rear tyre blew after earlier contact, spun at 280 km/h through The Chase and rolled six times in the sand-trap before coming to a stop. Coulthard has failed to replicate his 2008/2009 speed with only three respectable results being a seventh in race 5 of the championship, at the 2010 Clipsal 500 an eighth at 2010 Falken Tasmania Challenge and another 5th at the Sydney Telstra 500. In 2011, Coulthard continued racing with Walkinshaw Racing, driving the No. 61 Bundaberg Racing Team VE Commodore.
In 2012, he left Walkinshaw Racing and moved to Brad Jones Racing. Coulthard won his first V8 Supercars race at the Symmons Plains event in 2013, he went on to win a further 2 races and scored 9 podium finishes that year. He finished the year in 6th Place. 2014 was not quite as successful for Coulthard, with only one race win and five podiums on the way to 8th in the Championship. In 2015, coulthard opened the year strong, with a podium in the first race at the Clipsal 500 and a win in the second. He went on to score another 7 Podiums in the year, placing 7th in the championship.
Coulthard left Brad Jones Racing at the end of the 2015 season to sign with DJR Team Penske, returning to a two-car squad after running only a single car in 2015. He went on to place 12th in the championship. In 2017 he won 4 races en route to a career best 3rd in the championship
