For 1999, Schwager made a change to his racing career and moved from Europe to Japan, entering the Formula Nippon series as well as having his first taste of grand tourer racing by entering the All Japan Grand Touring Car Championship (JGTC) series in select rounds partnered with Hideshi Matsuda driving a Team Taisan Porsche.

This early success in JGTC led Schwager to concentrate solely on the series, moving to the top GT500 category and partnering Daisuke Ito at Nakajima Racing in the Mobil 1 Honda NSX.

Schwager remained with Honda into 2002 but turned to the Mugen Motorsports team before switching to the Toyota Supra in 2003 with SARD.

This expanded in 2008 when Schwager entered the new ADAC GT Masters series in a Callaway Corvette and won three races.

Schwager and Pastorelli also participated in select rounds of the American Le Mans Series for West Racing.