Switched to 5W-30 from 0W-20

It's been over a month now since I switched to 5w30 in my car. It's hard to tell the difference really, but it seems to be a little quieter overall. Less clattering noise, especially on cold starts. I doubt I'll go back to 0w20.
 
Interesting thread. I'm surprised they haven't come out with a thinner oil for cold temperature like -5W20 or -10W20. I used 0W30 semi synth way back in 1980! I also find it hard to believe that the same 0W20 oil can be used in Death Valley and Anchorage all year long...
 
No need. Mazda Moly 0w20 pour point is -54C :) Other quality oils 0w20 go to -40C as well. Thats ambient temp. lower than that temp and you get other problems. Need engine heater. The canadian Mazda dealers offer one for the CX5. The oil is quite capabe to withstand -30C and +50C but the oil change intervals would be shorter.
 
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Interesting thread. I'm surprised they haven't come out with a thinner oil for cold temperature like -5W20 or -10W20. I used 0W30 semi synth way back in 1980! I also find it hard to believe that the same 0W20 oil can be used in Death Valley and Anchorage all year long...
Ha ha. It's called selling to the masses and keeping it simple, or as wlong01 said, the dumbing down in America (and everywhere else).
Try to remember, people like us that join car sites and actually take an interest in what's best for our vehicles, are in the small minority. Mazda doesn't sell cars to the motoring enthusiast. 99% of buyers are daily grocery drivers and soccer moms. They have no interest or knowledge about what type of oil goes into their cars. You could put a barrel of used oil in there and they wouldn't be any the wiser. Try to talk to the majority of CX-5 owners about 0w20 vs 5w30, and they'd look at you like you're from another planet.
Mazda says 0w20 in North America for no other reason than it's easy to understand and simple.
If they started trying to recommend different grades of oil depending on what state or province you live in, or what the weather is going to be like tomorrow morning, then it would open up a hornets nest. It's just not possible. Better just to specify one grade of oil, and call it a day.
 
Interesting subject. Never really payed attention to what type of oil my dealer uses but I've checked the last invoice and it's 0W20. Now, I live in a warmer part of the US, snow maybe once every 10 years, few inches... below freezing temperature, maybe few days a year, and that's barely below freezing. So, question for you guys: should I go for 5W? Maybe even 5W30 in the summer, when the temperatures goes frequently above 100℉/40℃ ?
 
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Interesting subject. Never really payed attention to what type of oil my dealer uses but I've checked the last invoice and it's 0W20. Now, I live in a warmer part of the US, snow maybe once every 10 years, few inches... below freezing temperature, maybe few days a year, and that's barely below freezing. So, question for you guys: should I go for 5W? Maybe even 5W30 in the summer, when the temperatures goes frequently above 100℉/40℃ ?
I've been happy running 5w30 in Colorado for 2 solid years now, both hot and cold. Runs great.
 
Pennzoil Ultra Platinum 5w30 is some of the best rated oil, slightly behind the crazy expensive Amsoil.
Walmart.com is usualy the cheapest
 
Interesting subject. Never really payed attention to what type of oil my dealer uses but I've checked the last invoice and it's 0W20. Now, I live in a warmer part of the US, snow maybe once every 10 years, few inches... below freezing temperature, maybe few days a year, and that's barely below freezing. So, question for you guys: should I go for 5W? Maybe even 5W30 in the summer, when the temperatures goes frequently above 100℉/40℃ ?

I drove for 4 years with 0w20 in Arizona. No problems even in warmer climates.
For warranty purposes its good to stick with 0w20. I have to agree though that 5w30 is better fit probably but Mazda uses 0w20 in US due to CAFE requirements. Thats for the non-turbo
 
My main complaint was my dealer using conventional dino oil in the turbo models, over synthetic 5W30. The 0W20 is synthetic already, as I don't think they can make a dino oil that thin. So, you non-turbo guys are already protected with a superior oil.
 
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I drove for 4 years with 0w20 in Arizona. No problems even in warmer climates.
For warranty purposes its good to stick with 0w20. I have to agree though that 5w30 is better fit probably but Mazda uses 0w20 in US due to CAFE requirements. Thats for the non-turbo
I've compared Mazda manuals from Europe vs USA. In the Europe's manual it says that the 5W30 oil can be used on non-turbo models, while in the USA's manual it says that it can be used only on turbo. So I decided to screw the CAFE requirements and I will ask the dealer to put 5W30 at the next oil service. I understand the requirement to make a car to achieve a certain mpg but that's not realistic. Each one of us has a different driving style, different mpg. I don't see how the CAFE thing applies to someone's car once the person bought it.
 
I've compared Mazda manuals from Europe vs USA. In the Europe's manual it says that the 5W30 oil can be used on non-turbo models, while in the USA's manual it says that it can be used only on turbo. So I decided to screw the CAFE requirements and I will ask the dealer to put 5W30 at the next oil service. I understand the requirement to make a car to achieve a certain mpg but that's not realistic. Each one of us has a different driving style, different mpg. I don't see how the CAFE thing applies to someone's car once the person bought it.

This is from the North American manual. I think you will be happier with 5W30, the engine definitely runs quieter.

0w20.png



5w30.png
 
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⋯ So I decided to screw the CAFE requirements and I will ask the dealer to put 5W30 at the next oil service.
The only thing you want to make sure is you ask your Mazda dealer to put in full synthetic 5W-30 oil for you and put it in writing on the invoice. There’re plenty of conventional 5W-30 oils on the market but not on 0W-20. Even Mazda’s OEM 5W-30 oil isn’t a full synthetic.

See post #30 above.
 
Interesting subject. Never really payed attention to what type of oil my dealer uses but I've checked the last invoice and it's 0W20. Now, I live in a warmer part of the US, snow maybe once every 10 years, few inches... below freezing temperature, maybe few days a year, and that's barely below freezing. So, question for you guys: should I go for 5W? Maybe even 5W30 in the summer, when the temperatures goes frequently above 100℉/40℃ ?
FYI, in simple terms:
Example 5W30: The W stands for winter, whereby 5W is the low temperature viscosity and 30 is the high temperature viscosity at 100 degrees Celsius. The lower the number before the W, the better the oil will flow at low temperatures.
 
FYI, in simple terms:
Example 5W30: The W stands for winter, whereby 5W is the low temperature viscosity and 30 is the high temperature viscosity at 100 degrees Celsius. The lower the number before the W, the better the oil will flow at low temperatures.
Honestly those numbers don't mean much, you need to look at the Technical specs for each oil, that will give you the real properties, for example Amsoil signature series oil, the difference between 0w30 and 5w30 is literally nothing. More for making people feel warm and fuzzy about buying oil that matches what the oil cap says on the engine.
 
I put 5/30 Mobile 1 in my CX 5 this summer. I can’t say I noticed any difference at all. I’m about to change the oil for winter and I’m going to put the Mazda 0/20 in. We spend a lot of time below zero here in the winter. Otherwise, either one seems fine.
 
Here's a video of the engine idling with 5W-30, for those of you using 0W-20. You can barely hear the engine, which is not the case with 0W-20. I can honestly say I notice a huge difference at idle and cruising speeds in my 2019 CX-5 AWD.

(File too large for forum).

 
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I still really like the switch to 5W-30. Hard to represent the sound on a video, on computer/desktop speakers (louder than actual).
 
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Where does it say 5w-30 is ok for USA models? I only see 5w-30 listed in the “except USA, Canada” section.
 
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