The pair already had World Cup victories in Igls and Konigssee under their belts but stretched their lead further atop the overall standings to send the home fans home happy.
The European silver medallists led after the first run but saved their best until last as they set a track record of 41.299 seconds next up.
Their total time of 1:22.654 minutes was 0.364 seconds ahead of Austrians Peter Penz and Georg Fischler in second.
Germans Toni Eggert and Sascha Benecken finished third on home ice and are now 60 points behind compatriots Wendl and Arlt as they are second in the overall standings.
A blistering first run from Natalie Geisenberger, meanwhile, was enough to hand the German a second-successive luge World Cup victory of the season.
The Olympic bronze medallist sent the home fans wild as her first run of 52.164 seconds was just 0.003 off the track record.
Geisenberger could only manage the second fastest second run but the damage had been done and compatriot Anke Wischnewski couldn't close the gap, finishing 0.123 seconds behind in second.
Geisenberger has finished second in the World Cup for the past four seasons but following her second win of this campaign currently sits top of the pile on 285 points, 40 ahead of Wischnewski.
And it was there was a German on every step of the podium in Altenberg as Corinna Martini's time of 1:44.766 minutes was good enough for third.