Since June, the Black Crowes have been on the road with Robert Randolph and the Family Band and the Drive-By Truckers. While the often social Crowes have, surprisingly enough, been slacking in the sit-in department, over the weekend the Truckers picked up the slack. On Saturday, while performing at Holmdel, NJs PNC Bank Arts Center, the Drive-By Truckers invited out Crowes guitarist Marc Ford during its opening set. Ford added an auxiliary axe to the Drive-By Truckers original, Danko/Manuel. The Drive-By Truckers will appear with the Black Crowes and Robert Randolph at Detroit, MIs DTE Energy Music Center Wednesday.