Thanks for the note, I didn't think there would be that much difference in color of oil - apparently I stand corrected
As for the 12k mark to change synthetic, is it worth the extra cost of synth if it is only about 2x the mileage from the normal service life of dyno oil? (assuming the factory recommended 5k-7.5k interval)

 

The cost issue is a rather complex one, including (but not limited to) the following considerations:

• I have long been a consumer of synthetic oil due to the fact that I'd owned several turbocharged cars, cars which went over 100,000 miles on the factory turbochargers while friends and acquaintances of mine (all of whom used conventional oil) with the same engine were having their turbos replaced in the fifty to sixty thousand mile range.
• At the time I started the UOAs and the subsequent switch to 12,000 mile OCIs, my wife and I were driving a combined five to six thousand miles per month (our places of employment were in opposite directions no less).
• As I put a high value on my time, I consider it part of the expense of doing an oil change. By extending my oil changes from 7,500 miles to 12,000 miles, I reduced the frequency of oil changes from an average of one change every five to six weeks to one every nine or ten weeks. Fortunately the miles we drove were fairly evenly distributed so I could do both cars at the same time and further spread the calendar gap between oil changes to every four to four and a half months.

So, while the use of synthetic oil may not have been cost effective from an absolute dollar out of pocket perspective (although it was pretty close), I believe I was way-way ahead of the game when my personal time is factored in. That and when I pulled the heads off of one of those cars (chasing an elusive coolant leak which turned out to be a faulty "O" ring elsewhere in the engine) when there was 143,625 miles on the clock, I was delighted to see all six cylinder walls still sporting their factory honing marks.

 

I checked out my local Auto Zone and they didn't have any 0w-20 grade oil...The helpful employee suggested to buy Mobil 1 5w-30. A few questions have arised...

Would this cause any harm using this grade instead of 0w-20 (manufacturer's suggested grade) or void any warranties?

If yes, what do you suggest I do? I'm thinking of checking out other auto stores if they have the specific grade suggested by the manufacturer.

I don't think it stated how many quartz I should use from the manual. My Dad states 4 cylinders requires 4 quartz... I think the regular bottles are 1 quartz. Please correct me if I am wrong.

Lastly, does any type of filter matter? I noticed there were different brands that vary by price. For example, Mobile 1 and Bosch cost more than the standard oil filters.

I did a quick research of oil filters (first link on google search "What does the oil filter do?"). It compared a typical cellulose filter media vs SynLube MicroGlass media. The typical cellulose looks less tangling than the Synlube filter. It also suggests to use OEM filters instead of other type of filters b/c technically OEM's are designed for the car. Is this true?

 

Bad advice; you should run either 0W-20 or in a pinch 0W-30. That said, every AutoZone I've ever visited regularly carries Mobil 1 0W-20, as does Walmart, and Pep Boys; if your local store doesn't have it in stock, ask them to order some for you.

From a purely legal perspective, Mazda would have the right to deny you any engine repairs under warranty if they ask for oil change receipts and discover you've used the incorrect weight.

By all means; 0W-20 is a very commonly used grade of Mobil 1 (and now a few other brands) and becoming moreso every day.

Last time I checked, the Owner's Manual specified 4.5 quarts for the 2.0 liter engine and 5.3 quarts for the 2.5 liter mill. The number of quarts is in fact specified in your Owner's Manual.

If you're going to use the dinky sized oil filter Mazda specifies and/or extend your oil changes beyond 7,500 miles, then yes, filter quality matters. If you're going to change your oil more frequently than the recommended interval, pretty much anything will do. FWIW, the spin-on mount Mazda uses on some of their cars matches the mount Chrysler and Ford use; as such, I've opted to use a larger diameter Chrysler/Ford filter on my Mazda3.

I would recommend the use of an OEM filter over that of an el-cheapo brand, but oil filters are in fact fairly generic (OEM filters included) in both size and filter media. Mobil 1 filters are very good, but a bit over-kill if you're sticking with the standard oil change interval.

 

What section did you get the quartz info. from? I'm having trouble finding it in the manual. I also bought 6 quartz of Mobil 1 advance fuel economy oil with mobil 1 filter. All together it cost just above a little over $70.

Have you had any experience with the fuel economy version?

 

I don't remember off the top of my head where I saw it in my Mazda3 Owner's Manual, but for most cars there's usually a section called "Specifications", and under that there's a sub-section called "Capacities".

I've been running Mobil 1 "Advanced Fuel Economy" in my Mazda3 since its first oil change (which happened over 50,000 miles ago).

 

When checking the dipstick for oil level, the oil film should really be noticeable right? Meaning the tip should be drenched in oil. I'm asking b/c I'm having trouble looking for the oil level. My Dad dropped only 4 quartz and the dipstick showed the oil level at the middle on Sunday. When I checked this morning, I couldn't figure it out. The film wasn't as noticeable. Also, wouldn't the engine light turn on if there isn't enough oil or does it only turn on when a real major issue occurred?

 

A few comments and or questions:

• When you checked the oil after four quarts were put in, had you A) replaced the filter, and B) not yet started the engine?
• If the answers to the above question is "Yes", then you need to add another quart to account for A) the oil which is now in the filter, and B) the fact that in my experience, the Mazda oil spec brings the oil level up to is about a half of a quart shy of the "Full" mark on the dipstick.
• The "engine light" has nothing to do with "enough oil" being in the sump. Why? Because four quarts is usually enough to supply the engine with enough oil pressure to keep things above the mininum.

 

The filter was replaced. I think we did turn the engine on before checking the oil. Perhaps this is the reason the oil level was at medium level when we checked on Sunday. I'll check it again when I park at school later tonight.

 

the dipstick is horrible to read unless the oil is black. i've put holes & notches in the end of the dipstick so I can see where the level is a bit better.
as for quantity, "specifications" section under "capacities"
just looked at the 2011 manual and it shows 5.3 quarts for the 2.5L with oil filter change (4.5Q for the 2L, and 6Q for the 2.3 turbo... all with filter quantities)
https://www.mymazda.com/MusaWeb/pdf/..._Mazda3_OM.pdf