let see if i can get yelled at, my son as well as two very good friends are heavy diesel mechs, one (not my son) has well over 15 years with companies like empire, schwabb, red mountain machinery. all concerned say the same thing rotella while a great oil for diesels (ask any trucker) should not be used in a gas burner due to the detergents used in it to help fight the soot in an oil burner.
That's what I always thought as well. But looking at the Shell Rotella website the oil is rated for gas engines-"
API CJ-4, CI-4 PLUS, CI-4, CH-4, CG-4, CF-4,
API SM, SL, SJ, SH "