Well that's damned infuriating. I poured through the manual and the only specs say SAE30, 10W-30 10W-40 and must meet API Service CD, CE, or CF. I checked Mobil-1 site.
Per their site:
According to ExxonMobil, Mobil 1 10W-30 is of the following quality level
General Motors GM 4718M
General...