yeah mobil 1 5w30 all year round but again it doesnt get cold here either. Ran right along with a mobil 1 filter as well. I love mobil 1 and the filter. You could literally see the difference in oil pressure with the mobil 1 vs the STP filter. This was tested out on a buddies 240 with an oil pressure guage. I think at startup initially it saw around 20psi more oil pressure and then with the engine fully warmed up at idle it was seeing over 10psi more pressure. Cant argue with the facts