Hi, this is probably a common question, but is it ok to use 5w-30 vs 0w-20? (Full sythetic). I normally do my own maintenance, but had a coupon to get tires rotated for $10, and a $10 off for oil change. Boy, do I regret that. $98 for synthetic oil change!, and they put in 5w-30 instead of 0w-20. Steering vibrates some now too, so guess a tire(s) out of balance.(never going back to tires plus.)
Anyway, I've read 5w-30 isn't such a bad idea for the hot summer, and won't hurt anything. If it was winter, I'd have them replace it. Guess I drew the special needs technician to work on my car. It clearly shows 0w-20 on the oil filler cap.
Thoughts? Leave as is? I change every 5000 with full synthetic.
Not sure if I've posted before but do enjoy the forum.

 

No problem with using 5W-30 year around. The turbo engines call
for the 30 weight oil and the engines themselves are nearly identical.
I've used 5W-40 on a long trip with no problems.
My 2¢

 

The term "won't hurt anything" should not be used to judge any aspect when asking a question like yours? NO ONE has the insight to know all the driving enviroment and the way someone drives or takes care of their auto to be able to say that phrase.


As for using other viscosity my advice is naturally if you have any question about it stay with what the recommended viscosity is. However, if you use the charts for what viscosity to use in your operating environment which is more about temperatures you will always find the best viscosity to choose.

So looking at the average summer temperatures in Wisconsin you can see ........

 

Dobbler Welcome to the forum

 

Me, I'd take it back and tell them to put the correct oil in at no charge.
And I'd make sure I watched them do it.

 

But does not this get into the debate of what is the correct oil. Globally is differs even from what the recommend viscosity.

The oil viscosity charts still are the best way to determine what viscosity to use .

 

I don't normally disagree with you and while your statement is all well and good and I understand what you are saying, but that isn't the point I was making and is not what Mazda says to do.
The 2016 Mazda owner's manual states the following.
U.S.A. and CANADA: Use SAE 0W-20 engine oil. Mazda Genuine Oil is used in your Mazda vehicle. Mazda Genuine 0W-20 Oil is required to achieve optimum fuel economy.
For maintenance service, Mazda recommends Mazda Genuine Parts and Castrol® (U.S.A. only).
Meaning the service center the OP used, did not follow the manual nor did they ask him if they could switch viscosities.
Which means they either didn't know what the Mazda manual viscosity states or they didn't care.
While they may have one's "best interests" in mind, I would tear a new excrement exit for any type of service person who didn't care about a service manual or asking me before they interject their personal choice on my vehicle (or whatever it is they are working on).
My local wrench will not substitute fluids, switch out any OEM part or deviate from specified repairs without asking me first.
I'm certain you would not accept substitutes from your parts suppliers without them asking you first, even if they may know more about their products than you do.
Poor customer service is why I would take it back and demand they change the oil to the 0W-20.
Then I would never back there.

 

It has to do with emission and average MPG Federal requirements that must be met by the auto manufacture not what is technically "required" to use for any specific oil viscosity. I do understand that many do not realize that a little "tweeking" with oil can meet those federal emission requirements only to sell in some countries like the USA .
Dealerships are not required to use any Mazda recommended oil viscosities or type unless the exact wording say just that. Required.
So in that understanding by the law at least in the USA the oil the op received at MAZDA is OK!

This can also be supported by contacting Mazda or any other auto manufacture and wording correctly will get the same response as I just did, but maybe with better syntax and sentence structure skills. LOL

I have been in a couple suits supporting a person(s) needing to get a engine replaced under warranty that was at first disallowed because of the choice in viscosity oil. However, it was agreed by both parties and went into useing arbitration ation I presented this argument as I posted some of the information in the last 2 responses here and the auto manufacture declined to continue the suit and replaced the engine. Nice 454 Crate engine. Btw. LOL

 

I want to add that a customer has the right to ask for a specific oil they want in there engine ,transmissions , rear ends, etc, however the independent service shops even the dealership has the right to charge more for those requests not normally used in those service procedures.
It is the customers responsibility to know in advance what oil is going to be used and even in some case what parts are going to be used prior the service.
Ask questions before you sign and agree for the service.

 

Always!!!