Favorite Oil in Sky Active 2.5L engine ?

*So , the turbo must use premium 91+ octane ? ... That can be expensive today - if that's the case I would rather have the 2.5L Sky Active non - turbo which can run on 87 octane .
Basically yes, the manual says lesser octanes can be used but a reduction in performance will occur. On one of my trips last year I had to use 87 as it was the only fuel available where I stopped. It operated fine and power was still more than adequate but it took a good mpg hit compared to my other premium fuel fill-ups. I haven't found any credible info on whether using lower octane fuels for extended periods will cause the possibility of any damage or accelerated engine wear. But it would be nice to know. Right now I keep close to my Costco store that sells premium for about the same price that other dealers sell regular. Last month we took a trip from Denver to Ohio, but with my wife's Mazda3 to save a few bucks. Good thing we did because in many places premium was as much as a dollar more per gallon than regular and 60 to 75 cents being more typical. At my Costco the difference tends to be about 40 to 50 cents for top tier premium fuel.
 
My old account got deleted out of slow activity. Anyway, is there any truth to info that seems to get repeated on the internet about the 2.5 Mazda engines burning oil? There are comments about bad valve stem seals, but does that lead to heavy oil consumption in an otherwise low mileage engine?
 
My old account got deleted out of slow activity. Anyway, is there any truth to info that seems to get repeated on the internet about the 2.5 Mazda engines burning oil? There are comments about bad valve stem seals, but does that lead to heavy oil consumption in an otherwise low mileage engine?
Well that's kind of strange I know there are several people on here that have the 2.5's me included although it to new to be suffering from the issue but serious I can't remember and posts on Mazda that were oil burners to the extreme. Does anyone else have more to add?
 
Well that's kind of strange I know there are several people on here that have the 2.5's me included although it to new to be suffering from the issue but serious I can't remember and posts on Mazda that were oil burners to the extreme. Does anyone else have more to add?
Without a link… Hmm.
 
Well that's kind of strange I know there are several people on here that have the 2.5's me included although it to new to be suffering from the issue but serious I can't remember and posts on Mazda that were oil burners to the extreme. Does anyone else have more to add?


This is the first I’ve heard of this. Possibly internet banter without any source?
 
It's the 2.5 turbo that has a valve stem seal durability prb, I believe in a certain VIN range. Not the naturally aspirated 2.5 Skyactiv. Apparently, as well, the 2.5 non turbo can suffer from a cyl head casting flaw, leading to coolant entering the crankcase (obviously not good, resulting in total engine loss very quickly). This is not common though. I don't know what VIN range, for that...

As to valve stem oil burning, you just wouldn't believe how few people check their oil level routinely. I do, every 2nd or 3rd fill-up...
 
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IF memory serves, no guarantee these days, the valve seal problem is showing up
in 2021 and 2022 model years. A re-design that wasn't tested long term would be my guess.

My 2¢
 
And overall build quality as well. My 2016 Mazda6 is as well-built as any vehicle I’ve ever owned.
Oh, definitely! Mentality coming into this purchase was, "buy a vehicle that (I hope!) will be largely trouble-free beyond standard-ish maintenance items for ten years." Time will tell if I get what I hoped for. :)
 
Oh, definitely! Mentality coming into this purchase was, "buy a vehicle that (I hope!) will be largely trouble-free beyond standard-ish maintenance items for ten years." Time will tell if I get what I hoped for. :)
Be confident. :)
 
It's the 2.5 turbo that has a valve stem seal durability prb, I believe in a certain VIN range. Not the naturally aspirated 2.5 Skyactiv. Apparently, as well, the 2.5 non turbo can suffer from a cyl head casting flaw, leading to coolant entering the crankcase (obviously not good, resulting in total engine loss very quickly). This is not common though. I don't know what VIN range, for that...

As to valve stem oil burning, you just wouldn't believe how few people check their oil level routinely. I do, every 2nd or 3rd fill-up...
That is correct. As you stated it's not that common.

The turbo doesn't not need premium, but to get the full 250hp you will need to use it.
 
IF memory serves, no guarantee these days, the valve seal problem is showing up
in 2021 and 2022 model years. A re-design that wasn't tested long term would be my guess.

My 2¢
The issue was a faulty valve stem seal change that occurred sometime in 2020-2021.
 
I tried to get OEM Tokyo Roki 66mm/14 flute filters for my Mazda, but the source simply dried-up. Wish I had a contact in Japan... Surely Roki in Japan doesn't supply OEMs only... but also the Japanese market too?
Gomiata.com still seems to be selling the Made in Japan Mazda filter as well as the Thailand filters if i'm not mistaken.
 
I'm not a fan of how fast Mazdas rust. They seem to be made from really cheap materials. Maybe the new ones are better but I don't think I will buy another one.
 
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