86 octane top tier or 87 octane not top tier?

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I've got a 2024 Mazda CX-5 non turbo. According to the manual, you're supposed to put in 87 octane or better.
Most all the stations where I live only have 86 octane and I'm told it won't make a difference to use that.
There are a couple stations with 87 octane, but it's not top tier.
QUESTION: Should I go with the 87 that's not top tier or get the top tier 86?
 
Welcome to BITOG 🥳

The top tier isn't really that important. Get the 87.
Thanks. 👍
I've been using the 87, but read that top tier gas contains detergents that help keep your engine clean which can reduce carbon buildup and deposits on the intake valves.
So I wondered which was the best way to go.
 
You can also add something like Techron every 6K miles or so, and get similar or better results than the top tier amounts. Hyundai and Subaru both recommend using a gasoline additive in that mileage frame anyway. Don't know what Mazda recommends, but it is probably in your owner's manual.
 
I've got a 2024 Mazda CX-5 non turbo. According to the manual, you're supposed to put in 87 octane or better.
Most all the stations where I live only have 86 octane and I'm told it won't make a difference to use that.
There are a couple stations with 87 octane, but it's not top tier.
QUESTION: Should I go with the 87 that's not top tier or get the top tier 86?
Where are you located?
 
Thanks. 👍
I've been using the 87, but read that top tier gas contains detergents that help keep your engine clean which can reduce carbon buildup and deposits on the intake valves.
So I wondered which was the best way to go.
That doesn't mean that non TopTier doesn't contain the same detergents. There's just no guarantee of it. I don't use TopTier gas. I've never had any problems.
 
Thanks. 👍
I've been using the 87, but read that top tier gas contains detergents that help keep your engine clean which can reduce carbon buildup and deposits on the intake valves.
So I wondered which was the best way to go.

Even the bottom tier gas has detergents required by law. Never use less than 87 octane.

And as others pointed out, you can always use some additive such as Techron. Other good ones are Redline SI-1 and Gumout Regane.

You can also add something like Techron every 6K miles or so, and get similar or better results than the top tier amounts. Hyundai and Subaru both recommend using a gasoline additive in that mileage frame anyway. Don't know what Mazda recommends, but it is probably in your owner's manual.

This.
 
Thanks. 👍
I've been using the 87, but read that top tier gas contains detergents that help keep your engine clean which can reduce carbon buildup and deposits on the intake valves.
So I wondered which was the best way to go.

All gas has at least the EPA minimum for detergents. The top tier just has more, or a proprietary blend. I usually use the cheapest non-mom/pop shop around (usually speedway or BP, sometimes 89 or 93 if it's payday LOL) and run a bottle of Techron once every 30k miles or so before an oil change.
 
What's your altitude? Usually they only market 86 above a few thousand feet.

I'd see about trying them both under similar circumstances.
Lubbock, TX altitude is 3,202. The only stations with 87 in town are DK and it's not top tier gas.

What's your altitude? Usually they only market 86 above a few thousand feet.

I'd see about trying them both under similar circumstances.
 
That doesn't mean that non TopTier doesn't contain the same detergents. There's just no guarantee of it. I don't use TopTier gas. I've never had any problems.
Top Tier doesn't make detergents. One pays to use their signage and subject to possible audit of fuel purchases to ensure one is selling Top Tier's minimum quantity of the detergent you are using.

Top Tier specifies a minimum quantity for every EPA approved detergent. It varies with each detergent.

There is no reason a gas station operator can not use Top Tier quantity without paying Top Tier, just can't say "Top Tier".

There is no assurance the base gasoline is any better, other than Top Tier requires a minimum of 8% motor grade ethanol. If it is "ethanol free" then it can not be sold as Top Tier.

The whole point of Top Tier is to convince you that small brands of gasoline are as good as Shell and Texaco/Chevron. And to line the pockets of Top Tier's owners.
 
"Top Tier" is nothing more than a deposit formation standard developed by GM because some of their engines had problems with valve and combustion chamber deposits.
Most engines didn't and don't have these problems.
Most currently available gasolines would meet this standard and their marketers don't bother with the expense involved in certifying for it, since the testing involves an actual engine bench test and weighing of any deposits.
Anyway, at your altitude an 86 octane fuel would be fine.
 
"Top Tier" is nothing more than a deposit formation standard developed by GM

....and a slew of other manufacturers. It just wasn't GM. Get your facts straight before spewing nonsense.

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Results of 3rd party testing:

expense involved in certifying for it, since the testing involves an actual engine bench test and weighing of any deposits.

Again, complete nonsense.

 
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