Originally Posted By: CATERHAM
Originally Posted By: Char Baby
I like 5W30 better than any 5W20 that I have used thus far, simply for the smooth(er)/quiet(er) operation and the MPG is the same with either grade. I have my favorite oil(s) for this particular engine(2.0L).
used as a DD and nothing else. It's driven responsibly with very little aggression. I'm sure that syn oils would be a favorite in the engine if the car was drive harder.
The smoother/quieter is a subjective assessment which many including myself have never experienced in fact the opposite is my experience running heavier oil.
What is fact is the lower fuel economy you get with the heavier 5W-30 oil; the 1-2% savings with a 20wt is just too small accurately measure and therefore for most to notice.
Since the vehicle is driven conservatively that's all the more reason to run a 20wt oil.
But hey, to each their own.
Well, when running 5W20 oils (in which I still have a stash of BTW for this Mazda3), there is a noticable coursness(SOP) in the engine and too, believe me when I tell 'ya, there is very, very often, a MPG drop although very small, it is consistant over the OCI.
And the best that I can say for the 5W20 is that there is no change in MPG and trust me when I say; the 5W20 is never better in terms of MPG than the 5W30, in which I thought there would be in this engine(2.0L)!
With 5W20, I do notice some MPG improvements(small) in my other vehicle but, they too are noisier in their operation. Not loud mind you, just more audiable!
Keep in mind too, that I am speaking, brand for brand of all the motor oils that I have tried. Hav DS, GTX, VWB etc; 5W20 vs. 5W30. Or even jumping around from brand and weight. I have enough MPG data to substantiate this on all of our vehicles.
Also, I notice MPG differences between brands of gas which could be the inacuracies in the pumps(which I doubt, due to them being monitored on a regular basis by an outside agency).
But, as you mentioned, to each his own!