how do i choose a OCI? 06 mazda 3 2.3L with Castrol Edge Extended Performace + Mobil1 EP filter

Sep 23, 2017
hey guys sorry im a newby to oci's and everything, i got both of these on sale so why not.
I went with
castrol edge extended performance 0w20 (the 0w because in canada we get down to -40 degrees in the winter) +
the best filter i could get on sale which was the mobil 1 extended performance m1c 153

it seems like both of these advertise like 20,000 km intervals but i assume it depends on vehicle and driving conditions
I know i picked a thin oil (w20) but idk its hard for me to move away from manufactuer specifications so my main concerns for my oci are the following
1. i live in a small city so all my trips are short short city driving strictly with idling, i dont really make many long trips tbh (rip my battery)
2. in the winter it gets really cold, i always plug my block heater in but still (i tend to idle a bit extra in winter to warm the car)
3. our summers get super hot like near 100f

as long as the oil doesnt shear i am willing to run as long as yall recommend

so what do you think a safe bet would be?

I guess it depends on how much you drive in a year? if you drive less than 20000km/yr I'd go a full year on it, the 2.0/2.3/2.5L are super easy on oil.
I guess it depends on how much you drive in a year? if you drive less than 20000km/yr I'd go a full year on it, the 2.0/2.3/2.5L are super easy on oil.
thanks for the reply! i was just basing it on km's or does time matter do? i guess more heat cycles means more shearing ?

in a year prob about 10,000 kms about but i wanna ensure im not shearing the 0w20 because its already thin
Mechanical shear of the oil (actually the VII) is rarely a problem.

And I don’t know what “more heat cycles” has to do with it?
I don't know if this will help you much but I have been doing yearly changes on mine with 5w-30 synthetic or blend with no issues, but I only drive it around 5k miles per year.
Disregard everything on this site including my response.
Follow the OEM recommended oil change interval.
Complete a used oil analysis at any of the well known oil analysis houses.
Continue to run the OEM oil change intervals until you sell the vehicle or run it 200k+.
how many miles or kilometers and engine running hours do you have. if you can get the hours divide the milage by hours. if your total goes to 25-30 miles equivalent per engine running hour your engine is closer to city and id stick closer to 7k miles or km equivalent tops. now if its like 20 miles or less then thats severe and i wouldnt go over 5k miles equivalent.

Now if you get like 50-60 miles equivalent or more per engine running hour then you're doing more highway and you could probably squeeze out 13-14k miles equivalent on that oil since your specific engine isn't turbocharged or gdi and it doesnt beat on the oil. make it a twin turbo gdi and id reduce the oci by 50% in all scenarios to not have any issues since these modern vvt dohc TT gdi engines are pretty sensitive to dirty oil. that old engine not so much i have experience with the 2.5 version instead and it was a tank until it got flooded out.
What happened to the Mobil 1 HM you poured into it last week?

I have nearly the same car, 2007 Mazda 3 w/ 2.3 engine.
I don't drive much each year and just hit 90K miles recently. I've been changing the oil once a year, or about 6-7K miles. I use whichever synthetic oil I have been able to get on sale or rebate. I change the oil filter every other OCI because it's a cartridge and I don't feel like changing it every single time. I've used all sorts of filter brands, sticking to Fram Ultra's now because of their longevity and efficient filtration.
I used Xw-20 oils in the beginning, but switched to Xw-30 oils because I live in FL and super cold starting isn't an issue.
So far, my engine doesn't burn any noticable amout of oil. I think these engines are simple and are easy on oil, you should be fine using any quality oil in it.
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What happened to the Mobil 1 HM you poured into it last week?

he dumped it out at 100 miles because oil is cheaper than a new engine
Specs are 5W20 on mine in Canada, 5W40/10W40 in Europe. Pick whatever, I don't think that engine really cares.
I'd say a 0W is a must for Canada (depending on where in Canada too), it doesn't happen often but I've seen temps under -30° and cranking was slow 😂

Even with winter and short tripping, I think a full year OCI is easily doable. I don't know what transmission you have (hopefully manual), but if it's the FRN5 I'd do a "preventive" drain and fill.