I live in southern California, where for most of the year it doesn't get below 60 degrees or so. However, in the winter, we do have some mornings where the temps are below freezing, evidenced by frost on the grass and windshields.
The recommended oil for my '97 F-150 is 5w-30, which is what I'm using now. The only thing that bothers me about this grade of motor oil is that in a lot of the UOA's, it seems to shear down to a 20-wt. in 5000 miles or less. My truck has over 200,000 miles on the clock, so I think a 30-wt. is probably a good choice.
I've read Motor Oil 101, and while I know that not everyone here agrees with the good doctor's conclusions, I understand what he's saying about the thinnest oil being the best at startup.
So I guess my question is this: would it be OK to run 10w-30 during the summer months when the morning temp might be 70 deg. F or more (for less shear)? Would it be best to use a 0w-30 during the winter months when the temp is sometimes below freezing? Or should I just find a good 5w-30 and forget about it.
The recommended oil for my '97 F-150 is 5w-30, which is what I'm using now. The only thing that bothers me about this grade of motor oil is that in a lot of the UOA's, it seems to shear down to a 20-wt. in 5000 miles or less. My truck has over 200,000 miles on the clock, so I think a 30-wt. is probably a good choice.
I've read Motor Oil 101, and while I know that not everyone here agrees with the good doctor's conclusions, I understand what he's saying about the thinnest oil being the best at startup.
So I guess my question is this: would it be OK to run 10w-30 during the summer months when the morning temp might be 70 deg. F or more (for less shear)? Would it be best to use a 0w-30 during the winter months when the temp is sometimes below freezing? Or should I just find a good 5w-30 and forget about it.
