diywannabe
2010 CX-7
The 2010 CX-7 2.5L we just bought says 5w20 oil on the oil filler cap. It has 145,000 miles on it. Should I still use 5w30? Thanks
5w20 or 5w30?
- Thread starter diywannabe
- Start date
- :
- 2017 CX3 AWD
I believe you can. The owner's manual is a bit confusing though. If you flip to page 401 of the PDF, it tells you what to use depending on where you are. 5w20 was recommended for fuel economy.
I have a CX-3 and switched to 5w30 from 0w20.
I have a CX-3 and switched to 5w30 from 0w20.
diywannabe
2010 CX-7
I'm in Florida. It rarely gets below freezing and I've also read that in other countries Mazda recommends 5w30.
Lazy2.5
2015 Mazda 6 - AT - Tuned
- :
- Ontario
You can if you want to.
Or not.
Again. It doesn't make any difference. You're just going to get slightly higher oil pressures, slightly slower circulation during cold starts if it's cold out, maybe better protection when driving hard in hot weather.
I use 5w30 year-round here in Ontario. We get temps ranging from -30 to +38C at the absolute extremes.
Lazy2.5
2015 Mazda 6 - AT - Tuned
- :
- Ontario
Ok - I'll bite. Scroll down in the file attached in this post and you will find:
This is for a 2.0 CX-30. I don't care enough to find the specs for the 2.5L, but I'm sure it's the same.
So, no, this engine was not "designed around 5w30." It was designed for a wide range of oils (0W20-10W50).
- :
- 2017 CX3 AWD
For BMW/MINIs where the recommended weight is 5w30, folks go up to 5w40 by the same rationale as we choose 5w30 over 0w20. I remember not noticing any difference with 5w40 on my NA R56. Folks with turbos/superchargers seemed to prefer 5w40.
N7turbo
2023 CX-5 2.5T ... 2024 MX-5 RF GT
- :
- 2017 CX3 AWD
The OP has a 2010 CX-7 2.5. The owner's manual says use 5w20 for the 2.5 ltr engine, and 5w30 for the 2.3 ltr engine. If 5w20 is not available for the 2.5 ltr engine, then 5w30 is ok.
Good to know that newer engines can accommodate a wider range of oils.
Good to know that newer engines can accommodate a wider range of oils.
Attachments
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Lazy2.5
2015 Mazda 6 - AT - Tuned
- :
- Ontario
@N7turbo
In this link, it is confirmed that the 2.5L also is good for up to 10W50:
I strongly believe it is nonsense that all of these weights, including 0W20 are suitable for well beyond 40c.
I like the price for full synth. at Costco for two jugs of oil.
N7turbo
2023 CX-5 2.5T ... 2024 MX-5 RF GT
Bizarre that they would put that in the Mazda 6 manual for Australia and New Zealand.
In the CX-5 manual, the way they split out the countries is:
U.S.A., Canada
&
Except U.S.A., Canada
But based on temperature range, I'm not sure there is any benefit going from 30 to 40 or 50.
Lazy2.5
2015 Mazda 6 - AT - Tuned
- :
- Ontario
Basically, if you want to know what the actual requirements are, you just ignore completely what is specified for US & Canada.
Example: "North Americans are treated like small children who cannot check their tire pressures."
10W, 40,50 weights etc. Should serve some benefit in very hot climates. (Etc. Australia and New Zealand.)
Why does this matter?
A. 0W20 is obviously too thin for an engine that can handle up to 10W50, in cold weather.
B. The whole tight modern engine tolerances "argument" is a flat-out lie.
C. I'll emphasize this again. It's just oil. Regardless which one you pick, it will lubricate your engine. Just pick something in the middle, and make an informed decision based on your climate.
N7turbo
2023 CX-5 2.5T ... 2024 MX-5 RF GT
Well you do you, but I don't know anyone running oil that thick in a vehicle like this, regardless of climate. It doesn't make much sense to convince people they can do it when there won't be any benefit. The 20W and 30W oils are plenty good enough to prevent engine wear and hold enough viscosity for 5K+ mile oil changes. All you'll get with thicker oil is reduced power and fuel economy and slower oil flow at engine startup in the cold.
