Comparison of Royal Purple, Mobil1, Amsoil, and RedLine synthetic 10W-30 from a scientific point of view.
Everthing will be Royal Purple*/ Red Line*/ Mobil 1*/ Amsoil*/ Pennzoil* (for perspective)
* 10W-30, all synthetic other than Pennzoil
Viscosity@ 40C: 61.8/ 64 / 59.0 / 64.3 / 98 (Amsoil)
Viscosity Index: 148/ 136 / 147 / 177 / 105 (Amsoil)<=== most important!!
Pour Pt.(F): -49/ -58/ -65/ -60 / -22 (Mobil)
(lowest temp. you can pour it at, lower better)
Flash Pt.(F): 400/ 518/ 470 / 446 / 450 (Red Line, takes the heat)
(point the oil is ruined, higher is better)
Max. Oil Life: -12,000 / 10,000 - 18,000 / -10,000 / 25,000 / 5,000