Hi guys, I just changed the oil my self at 5k miles with the new Mazda Genuine GF-5 0w20 with Moly and I got improved gas millage. I am not sure if it is because it is first oil change (e.g. factory oil thicker?, different?) or its a result of the new oil (I believe that) but I immediately got improved gas mileage. Before I announce the numbers need to say that it is the Sport Manual (so you don't get shocked).
Before: 60 mph ~37-38 mpg, 65 mph ~ 34-35 mpg (50 miles highway, cruise control)
After: 65 mph ~40 mpg ( (50 miles highway, cruise control).
It is exact same route. First day after the oil change I though it might be a reversed wind, so I waited a few more days. Same results both direction (e.g. not downhill/uphill effect). This is in Chicagoland.
When I mixed it with some city driving (more like suburban driving) I currently have it on 37 mpg avg with ~40 mph avg speed. I should also say that I have about 100 pounds weight in the trunk at all times.
I am just blown away from this vehicle. I used it for business and thanks God I did not buy some heavy burner so called "truck".
I hope this tech is also reliable! Thank you Mazda!
P.S. Someone please confirm if you have similar results after the first oil change with different brand oil.
EDIT: For those unaware, this oil has perfect characteristics. Here is a detailed information about is. That is the reason to chose it. I had some hard time finding it with local dealerships for a price under $8 a quart. Currently, ROTO in Arlington Heights should have a case and should be able to sell to you for $8 (or less) if you get a dozen. You can also order onlie - the cheapest places I found is HandAaccesories (google it) ~$6.50 a piece + $20 shipping for a dozen and Arlington, VA Mazda (just a bit more, but if you live there you can pick it up and save the shipping cost).
UPDATE:
Almost a month later and I will have to disappoint you. I never managed to repeat those "crazy" numbers posted above: same route, similar conditions, same gas stations, same speeds. However, the week I got those ~40mpg numbers was very warm 70+ F. Since then, it has been always cold - under 45 F. My conclusion is that the car generally burns more fuel when its called outside. And while this will be no surprise for short city rides, I can not explain why it is happening on long highway trips (50-60 miles). And by that I mean a difference of 2-3 mpg on the current fuel gauge, and so the average (my car stays in a garage and I start and go - no warm up idle. In addition the highway entrance is 1.5 miles away). Could the heater ( I keep the interior pretty hot) be the reason?
Overall, it still has better fuel economy with the new oil, but difference is not as much as I though.
UPDATE 2
Just a quick update after 2 years (55k miles on the car):
I did put Castrol 0w-20 (It was super cheap at Walmart) in the fall of 2014 and definitely the car burns more fuel this Winter. Anywhere from 1-2 MPG difference.It fall down to 29MPG which is the first time I am seeing this. Previous winters it was 30-32. Summer 33-35.
Before: 60 mph ~37-38 mpg, 65 mph ~ 34-35 mpg (50 miles highway, cruise control)
After: 65 mph ~40 mpg ( (50 miles highway, cruise control).
It is exact same route. First day after the oil change I though it might be a reversed wind, so I waited a few more days. Same results both direction (e.g. not downhill/uphill effect). This is in Chicagoland.
When I mixed it with some city driving (more like suburban driving) I currently have it on 37 mpg avg with ~40 mph avg speed. I should also say that I have about 100 pounds weight in the trunk at all times.
I am just blown away from this vehicle. I used it for business and thanks God I did not buy some heavy burner so called "truck".
I hope this tech is also reliable! Thank you Mazda!
P.S. Someone please confirm if you have similar results after the first oil change with different brand oil.
EDIT: For those unaware, this oil has perfect characteristics. Here is a detailed information about is. That is the reason to chose it. I had some hard time finding it with local dealerships for a price under $8 a quart. Currently, ROTO in Arlington Heights should have a case and should be able to sell to you for $8 (or less) if you get a dozen. You can also order onlie - the cheapest places I found is HandAaccesories (google it) ~$6.50 a piece + $20 shipping for a dozen and Arlington, VA Mazda (just a bit more, but if you live there you can pick it up and save the shipping cost).
UPDATE:
Almost a month later and I will have to disappoint you. I never managed to repeat those "crazy" numbers posted above: same route, similar conditions, same gas stations, same speeds. However, the week I got those ~40mpg numbers was very warm 70+ F. Since then, it has been always cold - under 45 F. My conclusion is that the car generally burns more fuel when its called outside. And while this will be no surprise for short city rides, I can not explain why it is happening on long highway trips (50-60 miles). And by that I mean a difference of 2-3 mpg on the current fuel gauge, and so the average (my car stays in a garage and I start and go - no warm up idle. In addition the highway entrance is 1.5 miles away). Could the heater ( I keep the interior pretty hot) be the reason?
Overall, it still has better fuel economy with the new oil, but difference is not as much as I though.
UPDATE 2
Just a quick update after 2 years (55k miles on the car):
I did put Castrol 0w-20 (It was super cheap at Walmart) in the fall of 2014 and definitely the car burns more fuel this Winter. Anywhere from 1-2 MPG difference.It fall down to 29MPG which is the first time I am seeing this. Previous winters it was 30-32. Summer 33-35.
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