Martin Tomczyk will join Bruno Spengler in BMW's leading DTM team Schnitzer for 2014 as part of a reshuffle.
Tomczyk, who won the 2011 title when at Audi, had driven for RMG since he switched to BMW, but will now replace GT-bound Dirk Werner alongside '12 champion Spengler at Schnitzer.
BMW motorsport boss Jens Marquardt said RMG had underperformed in 2013, when it did not win any races.
It will have an all-new driver line-up for 2014, with Tomczyk heading for Schnitzer and former team-mate Andy Priaulx leaving the DTM for the Rahal Letterman Lanigan BMW United SportsCar team.
Instead RMG will run former sportscar star Maxime Martin and MTEK convert Marco Wittmann.
"BMW Team RMG undoubtedly failed to fulfil its potential last year," said Marquardt.
"We are sure that Stefan Reinhold's team will come back from the break reinvigorated and ready to get back to successful ways with Marco Wittmann and Maxime Martin.
"After a really successful first year in the DTM, Marco is definitely ready to take the next step."
RBM is the only BMW squad unchanged for 2014, with Augusto Farfus and Joey Hand staying on.