Originally Posted By: Number_35
Hello all -
After years of enjoying this site, I've finally joined. I have a couple of questions regarding the choice of motor oil for one of my vehicles, a 2009 Mazda 5 2.3 l inline-4 w/ 5-speed manual. I've searched the forum, and have gotten some good ideas, but would like to ask my questions anyway.
1. The manufacturer specifies 5W-20 year round...
To start with a thin oil (5W-20) and have it sheared down in a hard-working engine scares me a bit - I'd feel a bit better with 5W-30 in the summer, and perhaps 0W-30 in the winter...
.
Yes. Run the 5w30 in the summer... and use 0w20 in he winter. Should work well, a little extra thickness (protection...!) in summer, and better flow in the winter, with adequate thickness, because the oil will rarely hit normal operating temps in VERY cold temps, and is thus thicker anyway...!
I am of the opinion that modern oils allow a 20 grade to be " adequate " in most conditiions, but not necessarily the best choice available.... ! see CAFE...
Others argue that a 20 grade IS THE BEST CHOICE available. See Ford tests F-150 in Texas... To each his own...
However, seasonal oil changes aren't really required anymore, particularily with a quality synthetic...simplify things, and just run a 0w30 year round... even a 5w30 synthetic works fine in cold winter conditions... and... M1 0w30 is now available in Canada... try that... might be a good choice year round...!