This is more for people who live in states that have 4 different seasons. Ive always used synthetic 10w30 oil all year long. Spring, Summer, Fall, Winter. But I’m wondering if I should change the weights depending on the hot or cold seasons. Does it really matter if you always use synthetic or not?

 

Always use synthetic. It is superior. Use an appropriate weight for the expected temperature range you will drive in during the next few months. Those of us smart fortunate enough to live in nice climates are just fine with year-round 10W30.

 

I would not use a 10w oil if it gets below freezing. It's better to use a 5w or 0w oil all the time. All 0w oils are synthetic.

 

It's been several oil changes since it froze where I live. And they SAND the roads.