Synthetic Oil, oil change interval

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.
So you want to play maintenance schedule on oil change against Mazda’s recommendation? What other maintenance items do you want to make your own change schedule?

If you have your own opinion on maintenance schedule, that’s fine. It’s your own car. But in OP’s situation he has doubt about how often he should change the oil. The easiest way for him is simply to follow the recommended “Flexible” OCI. He drives 5K miles per year, you really believe he should change the oil 2 ~ 3 times per year? If he follows “Fixed” OCI instead of “Flexible” OCI which is only applicable to Schedule 2 in severe driving conditions, the interval is 5K miles or 6 months whichever comes first. OP still need to change the oil at 6 months interval where the car has only driven 2.5K miles. Most people would think OP should just change the oil once a year, which is exactly the “Flexible” OCI calls for.

Flexible” OCI is based on oil life monitor and the computer calculates the proper OCI with the cap of 7,500 miles or 12 months. Many CX-5 owners use 7.5K-mile Fixed OCI which most likely have longer OCI than “Flexible”. If you feel relying on computer is a bad thing, you still can change the oil anytime you want, using only the oil life monitor calculation as a reference. You have nothing to loose.
 
I drove my car just over 2,000 kms last year. That's only 1,300 miles.
When I went to my selling dealer, the service manager told me straight faced that I still need to change my oil every six months. That's an oil change every 650 miles. I changed dealers.
I'll leave it at that.
 
I drove my car just over 2,000 kms last year. That's only 1,300 miles.
When I went to my selling dealer, the service manager told me straight faced that I still need to change my oil every six months. That's an oil change every 650 miles. I changed dealers.
I'll leave it at that.

Canada follows Schedule 2. Changing the oil every six months/8000 kms is what is detailed in the Owner's Manual. Your service manager was just following Mazda's recommendations, likely so there would be fewer headaches on the off chance that you had engine issues and they had to file a warranty claim with Mazda Canada.

It certainly seems absurd to change the oil with such low mileage between OCIs. If it were me, since the car is still under warranty, I'd be changing the oil every 6 months, and once it's out of warranty, I'd get a UOA done at the 6 month period and use the results to determine future OCIs.
 
So you want to play maintenance schedule on oil change against Mazda’s recommendation? What other maintenance items do you want to make your own change schedule?

If you have your own opinion on maintenance schedule, that’s fine. It’s your own car. But in OP’s situation he has doubt about how often he should change the oil.
OMG I actually agree with ma boy Yrwei. :D
Following "the computer" is not going to be detrimental to your car at all. There's no way Mazda hasn't SLIGHTLY engineered the car to get you to change your oil a tiny bit earlier then you should. The dude that said "Don't follow the computer!" must think someone else put that computer there. LOL That's MAZDA'S computer! Mazda wrote the code for it. You think they'd have it err on the side of LESS oil changes? Come on man. And then what if I DO follow the Mazda Computer and the car sludges up on me and destroys my engine??? Guess who I am going to SUE?
It's the nanny days, brothers. The car companies do a LOT of stuff, companies in general actually, to not get sued! :D
 
OMG I actually agree with ma boy Yrwei. :D
Following "the computer" is not going to be detrimental to your car at all. There's no way Mazda hasn't SLIGHTLY engineered the car to get you to change your oil a tiny bit earlier then you should. The dude that said "Don't follow the computer!" must think someone else put that computer there. LOL That's MAZDA'S computer! Mazda wrote the code for it. You think they'd have it err on the side of LESS oil changes? Come on man. And then what if I DO follow the Mazda Computer and the car sludges up on me and destroys my engine??? Guess who I am going to SUE?
It's the nanny days, brothers. The car companies do a LOT of stuff, companies in general actually, to not get sued! :D
You're really naive to think that ANY company has your best interest in mind. You think they care what happens to your engine after the warranty is over? Lol that's ALL they care about it getting you past that warranty period and fact is that major engine problems won't show up until AFTER it expires and the damage is already done and you are SOL. All companies care only about their profit and bottom line, not you. You think telling people that their tranny fluid or coolant is lifetime and never needs to be changed is for YOU? Lol people are gullible and honestly don't think about anything these days.
 
You're really naive to think that ANY company has your best interest in mind. You think they care what happens to your engine after the warranty is over? Lol that's ALL they care about it getting you past that warranty period and fact is that major engine problems won't show up until AFTER it expires and the damage is already done and you are SOL. All companies care only about their profit and bottom line, not you. You think telling people that their tranny fluid or coolant is lifetime and never needs to be changed is for YOU? Lol people are gullible and honestly don't think about anything these days.
Some companies do care what happens to the engine in your car as they would love to sell you another one of their vehicles when the time comes.

Why do you think that major engine problems mostly happen after the warranty expires?

Time and mileage.

In general a car that gets driven a lot is more likely to have issues than one that gets driven very little. That's just logic.
 
You're really naive to think that ANY company has your best interest in mind. You think they care what happens to your engine after the warranty is over? Lol that's ALL they care about it getting you past that warranty period and fact is that major engine problems won't show up until AFTER it expires and the damage is already done and you are SOL. All companies care only about their profit and bottom line, not you. You think telling people that their tranny fluid or coolant is lifetime and never needs to be changed is for YOU? Lol people are gullible and honestly don't think about anything these days.
Go check the used oil analysis and see how many times we see excellent lab report for 7,500 miles of oil service. I’ve seen the lab suggested the CX-5 owners extending to 10,000-mile OCI based on the lab result. Toyota has been using 10,000-mile OCI for many years now. Mazda has 10,000-mile OCI on newer Mazda3 and CX-30 with the same 2.5L and 2.5T. My 2000 BMW 528i has up to 17,500-mile Flexible OCI although I change the oil a lot earlier than that. The longer OCI nowadays mainly is due to the much better synthetic oil performance. It also save your maintenance cost, and protect environment better. In fact, the main reason why the “Flexible” OCI started to be avilable in Europe and Asia for the best use of oil is because of the environmental concerns. You can’t use your past experience and think the same on oil change.

Again it’s your own car, you can change the oil how often you want. But I turn on the oil life monitor helping me to decide when do I need to change the oil for the best use of oil service life, usually a bit earlier at 30% oil life remaining, except last year changing the oil when “Oil change due” message showed at 12 months period since we drove a lot less during the pandemic.
 
It's the nanny days, brothers. The car companies do a LOT of stuff, companies in general actually, to not get sued! :D
While not a universal corporate perspective (opioid peddlers, Tesla) the point is well taken, but it is worth considering that "nanny days", whether nanny regulators or the nanny press, accrue to the consumer while forcing corporate competitiveness.
 
You're really naive to think that ANY company has your best interest in mind. You think they care what happens to your engine after the warranty is over?

Naive? How old are you? Are you old enough to remember the 80's well?
If not, let me share a story. In the 80's, the American car companies started to make cars that were damn near disposable. Honda and Toyota started going the other route: making cars that lasted longer and didn't need frequent expensive repairs. Can you guess what happened? Yep, the American public started buying MORE of those Japanese cars and FAR less of those American cars. The 'Big 3' didn't think Americans would EVER buy foreign cars in large numbers.
So the Big 3 realized something had to be done, they had to change, and they started to focus more on quality. Started making better cars. And it took DECADES for them to catch up. Started to in the late 90's. Made big process in the 0's. And are finally on par with the Japanese car companies today, though STILL a tiny tiny bit behind.
This caused LASTING damage to the American car companies. Would you believe TO THIS DAY there are still 100's of 1,000s of people that will not even consider American cars because of what happened 35+ years ago?
EVERY car company learned something back then. You think Mazda, or ANY car company, wants to be known as the one whose engines sludge after the warranty expires?

I am writing this with a smile on my face and not trying to be rude, brother. Joking around here just to make this one point: EVERY CAR COMPANY wants that reputation of having the long lasting cars. The RELIABLE cars. Having a reputation for cars only lasting as long as the warranty is a sure fire way to lose sales and maybe never recover them.
Only the expensive ones, like Jaguar and Alfa Romeo, and Land Rover don't seem to care.
Damn right Mazda going to nanny that oil change interval. ;)
 
Exactly why Subaru loves to promote this fact:

Built to Last​

96% of Subaru vehicles sold in the last 10 years are still on the road today, more than Honda or Toyota brands.

No, TCHMAN, the car companies don't care about ME... but they damn well DO care about their reputation.
 
Hate to tell you but Subaru is garbage the v6 boxer engines and their Transmissions are garbage. Blown head gaskets galore coupled with weak,slipping CVT transmissions and automatic transmissions just don't hold up. Manual transmissions on the other hand are solid and pretty bulletproof. And no car companies don't care about the individual person they only care about their bottom line and how much money goes into the pockets of the executives. They look to cut corners every which way and the American people are the victims of their shoddy craftsmanship with everything being subbed out to China. American workers don't have pride in their work any longer. Corporate greed, mergers and takeovers have led to the decline of American car companies for years and only getting worse. The only three car companies that actually care about their reputation are Toyota, Honda and Mazda. All other car companies that used to be are a shell of a name and aren't even manufactured by the same companies. Americans are fooled by names that don't represent their quality products any longer. I laugh when I see people driving Chevrolet traverses Dodge journeys and GMC acadias knowing that those rolling piles of garbage may not even make it to 100,000 miles before falling apart. People are pretty dumb when they spend their money and don't think long-term. Welcome to reality in 2021.
 
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Naive? How old are you? Are you old enough to remember the 80's well?
If not, let me share a story. In the 80's, the American car companies started to make cars that were damn near disposable. Honda and Toyota started going the other route: making cars that lasted longer and didn't need frequent expensive repairs. Can you guess what happened? Yep, the American public started buying MORE of those Japanese cars and FAR less of those American cars. The 'Big 3' didn't think Americans would EVER buy foreign cars in large numbers.
So the Big 3 realized something had to be done, they had to change, and they started to focus more on quality. Started making better cars. And it took DECADES for them to catch up. Started to in the late 90's. Made big process in the 0's. And are finally on par with the Japanese car companies today, though STILL a tiny tiny bit behind.
This caused LASTING damage to the American car companies. Would you believe TO THIS DAY there are still 100's of 1,000s of people that will not even consider American cars because of what happened 35+ years ago?
It's not just 35 years ago, the garbage that Dodge puts out is still garbage.

I always like to point out that there's a reason Chrysler went bankrupt. Twice.
 
Exactly why Subaru loves to promote this fact:

Built to Last​

No, TCHMAN, the car companies don't care about ME... but they damn well DO care about their reputation.
There is one important sense that every car company does care about you--they want brand loyalty, they want you trading for THEIR new new thing. Some do it with reliability, others with marketing, some with sketchy bleeding edge gadgetry. But in the end, the designers and manufactures who have gotten it right have raised the bar for everybody. Except for the lowest of the low models, the odds of getting 100,000 miles out an engine or transmission are pretty good whatever you buy if you do the recommended servicing. We could not say that back in the day.
 
There is one important sense that every car company does care about you--they want brand loyalty, they want you trading for THEIR new new thing. Some do it with reliability, others with marketing, some with sketchy bleeding edge gadgetry. But in the end, the designers and manufactures who have gotten it right have raised the bar for everybody. Except for the lowest of the low models, the odds of getting 100,000 miles out an engine or transmission are pretty good whatever you buy if you do the recommended servicing. We could not say that back in the day.
You do realize that what they want and how they do it before sale is different than how they treat you after sale right? Again they don't care how they get the market share, they just want to reel you in and play your mind to make you think like they care but in reality it's all smoke and mirrors because when it comes down to something breaking right outside warranty and they tell you to go pound sand, you're the sucker then. In today's world you have to be educated, informed and smart with your money and do all the research you possibly can before investing in something unless you're the type of person who gets rid of their cars every 3 years or sooner in which you're guaranteed to have mostly reliable transportation without expense. Take for example Hyundai and Kia. Sure they tout you in to their dealerships and get you to buy by offering a 5-year 60,000 mile bumper to bumper and a 10-year hundred thousand mile powertrain warranty but that really doesn't help if your car is broken down all the time and in the shop for repairs under warranty, and that's if you're lucky enough to make it to 100,000 miles without some dealer spewing BS on why something is broken and not covered under warranty when it should be and fighting with them to get it fixed. People buy Hyundai and Kia because they're good looking cars with feature value for a reasonable amount of money but in reality they are poorly designed low reliability vehicles with no resale value but people eat up the BS and think that the company actually cares about them. They only care about the short-term fiscal quarter and profits to make their investors happy, not long-term brand reputation. There's a reason why Honda and Toyota don't have to pull nonsense tactics, and that's because their brand can sell themselves. They cost a bit more but the return on investment far far substantiates the purchase on double and triple the longevity. And by the way, their quality and reliability has also been slipping in recent years but compared to American and European brands, the latter is absolute garbage. LMAO people need to wake up.
 
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I partially agree with Tchman2016, because all of the auto manufacturers are pushed to be more green. One way to be more green is to not recycle so much oil and trans fluid. So they set the intervals to be the longest without sacrificing the engine's or transmission's durability. But as stated, one can change their oil whenever they want. The more frequent the changes, the longer the engine will last, especially in the car's early life. It will just cost the person more money and be more inconvenient and make more polution. Personally I would never go a year on oil, with the two exceptions; that the car is not driven at all, or that the car is not going to be kept over 5 years.
 
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