The hosts opened the scoring in the 24th minute when Lewandowski's central run in the penalty area was met with an inch-perfect Serge Gnabry pass that left the Polish international with a straightforward point-blank finish.
Lukebakio leveled 11 minutes later when his deflected strike from range eluded Manuel Neuer. The goal was the Belgian's fourth at the Allianz Arena following last season's loan spell at Fortuna Dusseldorf, a joint-record among opposing players shared with Cristiano Ronaldo and Markus Rosenberg.
Grujic made it 2-1 for the visitors minutes later. The Liverpool loanee easily split two Bayern defenders to meet a lofted delivery from Vedad Ibisevic before sidestepping Neuer and firing into an empty net.
Lewandowski equalized from the penalty spot on the hour mark after VAR ruled Grujic to have daftly pulled the Bayern striker down away from the play.
Bayern applied heaps of pressure late to no avail. In the end, Niko Kovac's charges dominated with 71 percent possession and 17 shots to Hertha's six.
Borussia Dortmund, who are widely considered Bayern's only obstacle in extending the Bavarians' run of domestic success, kick off their 2019-20 campaign at home to Augsburg on Saturday.