Synthetic Oil, oil change interval

j45

:
Mazda 2016.5 CX5 GT
2016.5 CX-5 AWD 4dr Auto Grand Touring I've been getting dealer oil changes. They were using Castrol and now their own branded oil. I see I have been changing my oil too often. The car will be 5 years in late Oct. of this year. I have 24,000 miles on it. So in the fall it will be about 5000 miles per year.

I am using full Synthetic.

Should I just go the year between changes? I have been doing 2 or maybe 3 per year.

After this next (free) oil change I will most likely switching to my old mechanic here in town. If I have a choice with him, what brand of full synthetic should I use? Castrol was the recommended and used by the dealer, before they had their own brand.
 
2 or 3 oil changes in every 5,000 miles is excessive, in my opinion.
On the plus side, your engine internals are probably like brand new and nice and clean.
I'm in a similar circumstance like you with low yearly mileage. I drive even less than that actually. Just under 4 years at only 24,000 Kms (about 14,500 miles).
I do my oil changes yearly now. No need to change every 6 months like they want me to.
 
I just have it, the filter changed, and the tires rotated around 5,000 miles. I may go over it a 1,000 or so, but I figure it is a relatively cheap, but important part of maintenance.
 
I change mine every 5000 because it's easy to remember just by looking at your odometer.
 
Yes. With a synthetic, go *at least* a year. I run my synthetic oils 10k miles.

There is a mechanical engineer that builds engines, races and writes a blog. It's 540 RAT - Tech Facts, NOT Myths He has devised his own oil wear test, modelled after the ASTM test, but more severe, I think so it doesn't take so long. The blog is long and technical (and a delight to a geek like me), but near the bottom, he posts the ranking of every oil he's tested by the pressure it withstood. Search for “WEAR PROTECTION RANKING LIST”. Based on his testing, I chose Quaker State 5W20 Ultimate Durability when it was the 2nd highest performing oil he'd tested. It is now 23rd best. The new king of the hill is QS Full Synthetic 5W30, the replacement for Ultimate Durability. It withstood 15% more pressure.

Were I you, I would run the QS FS and change it at 10k miles. That's what I will do when I find the FS in a store.
 
$9/qt, while a little high, isn't horrific, considering it's got the extra Moly in it.

I posted that Amazon link to the oil for reference.

Yes, $9/quart is a bit expensive but not terribly so. I actually bought a case through Mazda Parts and Accessories Online | MazdaStuff and the cost came out to be ~$6.62/quart. Yes, there was a $36 shipping charge but I bought a bunch of other maintenance items at the same time.

I have a 2016 MX-5 that uses the same maintenance items as my CX-5 so that makes it very convenient when ordering stuff.
 
Any full synthetic these days that you like works fine. 5,000 is the right interval. Don't go over a years time as oil does oxidize over time, and the additive package breaks down.

That being said, for me, I use Kendall GT-1 Max. It's a Phillips 66 base oil product and exceeds ILSAC GF-6 requirements for new cars under warranty. Castrol just blends existing base oils and additive packages.
 
The dealer has it's own brand? What brand would that be, Mazda?

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:p
 
I will go from twice a year to 3 changes a year, because I do go on short rides a couple times a week. The oil from my 6 month change was so black.
I've been waiting for oil to go on sale at Walmart but it doesn't look like the oil I use will be going on sale. Last year it was on sale by July 25th.
 
Go to Costco and buy their brand GF6 full synthetic. 10 quarts for $24. Change every 4k on the 2.5T. especially with short trips etc which is considered severe service. Oil is cheap, engines are not.
 
You’ve been changing the oil 2 or 3 times per 5,000 miles in a year? That’s excessive to me with full synthetic oil.

To eliminate the guess work, why don’t you use “Flexible” OCI recommended by Mazda? Just wait for the wrench indicator and “Oil change due” notification and change the oil. The “Flexible” OCI can be UP TO 10,000 miles or 12 months whichever comes first on 2016 / 2016.5 CX-5 based on your driving habit. So in your situation with 5,000 miles per year, you change the oil once for 12 months.
 
Go to Costco and buy their brand GF6 full synthetic. 10 quarts for $24. Change every 4k on the 2.5T. especially with short trips etc which is considered severe service. Oil is cheap, engines are not.
For gen-2 CX-5 including 2.5T, Mazda recommends using “Flexible” OCI in Schedule 1 (normal driving conditions) and Schedule 2 (severe driving conditions) with maximum interval of 12 months or 7,500 miles. The only exceptions not to use “Flexiblr” OCI are:

-Extended periods of idling or low-speed operation such as police car, taxi or driving school car
-Driving in dusty conditions


So just let the on-board computer calculate the OCI for you with no guess work.
 
For gen-2 CX-5 including 2.5T, Mazda recommends using “Flexible” OCI in Schedule 1 (normal driving conditions) and Schedule 2 (severe driving conditions) with maximum interval of 12 months or 7,500 miles. The only exceptions not to use “Flexiblr” OCI are:

-Extended periods of idling or low-speed operation such as police car, taxi or driving school car
-Driving in dusty conditions


So just let the on-board computer calculate the OCI for you with no guess work.
Relying on a computer to calculate and tell you when to change your oil is not good practice IMO, and should not be used unless you like idiot lights. Too many people have absolutely no idea that oil is the life blood of their engine and it needs to be clean and functioning properly to protect their engine and for their engine to be reliable. Change your oil at a fixed Interval regardless and sleep well with extra insurance that your engine will be a reliable machine.
 
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