Engine lubrification.

[Alexx]

My car is my daily- driver and I live in Quebec. We have a hot summer and a cold winter. What oil would you recommend and why ? Right now, the crank- case is filled with 5W 40 synthetic fluids. Am I better with a thicker oil ? Perfomance is not important but realibility is. The engine has close to 265 000kilometers. Thanks for the time.

[tjts1]

Ur probably fine with 5w40 but if it keeps you up at night you might want to try a 0w30 or 0w40 synthetic for the cold starts in the winter, 5w40 in the summer. You won't have to worry about friction modifiers in a synthetic. These engines run cold anyway because of the massive finned aluminum oil pan and over engineered cooling system so you really can't go too thin in the winter. I imagine you have real winters in Quebec.
cheers