In my manual (2005 Sedan) it says to use 5W-30 oil. I had heard that it is a good idea to use 10W-30 oil in some seasons. Is this true? If so, which season is for which?


Also - Not sure if this should be a new thread - I have seen the Synthetic oil for 15,000 miles, but I can only find filters that go to 7,000. Do you need to special order 15,000 mile filters?

 

Personally i'd never wait 15,000 to change oil. Or 7000 actually. I'm still old school every 3000 for me. I supposed I might shift to 5000 if i was using synthetic. You'd probably be ok waiting 7000 miles though depending on how you drive. Check the oil after a few thousand and look at it's condition. The 10w-30 has higher viscosity characteristics than the 5w-30 when its cold. Both should have close to the same viscosity when they are hot. (not exactly, but close). If i can find the viscosity charts for the different weights I'll post them. Typically when people change oil weights they use the thicker stuff in the summer and the thinner stuff (5w-30) in the summer. Depending on where you live the temperature might not vary enough to make a difference either way. If i can find those charts, you'll see what i'm talking about.

 

I typically use the 5000 mile oil and change it around 4000. I drive alot (mainly highway - usually about 300~350 miles a day). I live in illinois so there is a pretty big differnce in the summer weather and the winter weather. From what you are saying, I should probably use 10W-30 in the winter and 5W-30 in the summer.

 

Actually just the opposite. 5w30 in the winter and 10w30 in the summer. 10w30 is a thicker oil and will flow a bit more sluggish when it is cold. Really unless you have an extreme change in weather i would just stick with 5w30. Most oil companies with extended oci's over 5000mi (15000 oci and up) ussaly suggest a filter change at 5000 and a top off. I run mobil1ep and still won't go past 5000 miles. For me its just a force of habit and thinking that no matter on the additives clean new oil is better then dirty. There is alot of quality filters out there I like wix, k&n/mobil1, supertech (ie walmart) and motorcraft. I know they sound strange they are good filters.

 

Here it is usually around 90 degrees in the summer and tonight it is supposed to be around 15 degrees. I would say it is a pretty drastic difference.

What to you suggest for the Winter? and for the Summer?