0w20 or 5w20

A while back the compression ratio was higher in the US than in Europe I think it was for the 2.0
 
Turbo engine has higher amount of air and gas as the turbo pressures air in when the throttle is opened and the computer raises the amount of fuel injected to give the right air/fuel ratio. More pressure on the piston and internal bearings, that is how more power is produced out the engine with the same displacement. All diesels have turbos to produce the high compression necessary to generate ignition without spark and most take a full gulp of air all the time just vary the amount of fuel needed to provide requested speed/output so high compression pressure all the time.
 
Time to hunt for some 20W-50 for we Texans....
I used to run SAE50 in my old 89 Prelude. With anything thinner, it would leak straight out of the rear main seal in a week!

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Turbo engine has higher amount of air and gas as the turbo pressures air in when the throttle is opened and the computer raises the amount of fuel injected to give the right air/fuel ratio. More pressure on the piston and internal bearings, that is how more power is produced out the engine with the same displacement. All diesels have turbos to produce the high compression necessary to generate ignition without spark and most take a full gulp of air all the time just vary the amount of fuel needed to provide requested speed/output so high compression pressure all the time.

Unless you absolutely need a turbo, i think there's less wear and tear on the NA engine running in permament sport mode than a turbo engine(with all the high temp/pressures).

I dont understand the reasoning behind a 4 turbo versus just using a good ole V6.

Or ressurect the in-line 5 for the mazda's. Imo, a 5 cylinder would have been the right balance of power for the CX5.

Now that i've dropped unsprung weight, the vehicle performs better and accelerates quickly but I think a 5 would be perfect.

Of course, now with hybrids coming out in the near future...
The torque, power and acceleration problem should be fixed by hybrid engine?
 
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I dont understand the reasoning behind a 4 turbo versus just using a good ole V6.

Weight and packaging. Reduced weight leads to better fuel economy, and a streamlining of parts across different models reduces material and R&D costs.
 
I'm specifically talking about the absolute fact that different areas of the world get different drivetrain options. The source is Mazda themselves.
Right, but I am talking about the engine, we are talking about engine oil. If we have the exact same 2.0L or 2.5L NA Skyactiv engine and they call for 0w20 in the US and 5w30 in Finland (I don't know where, just pulling a country out of the hat), that should tell you that both oils are acceptable for use.

In fact, my owner's manual says both oils are perfectly fine to use. So I am not sure what the hangup is here. Aside from maybe very marginal gas mileage advantage for the 0w20, I haven't seen the 0w20 gaining me anything. In fact, been much happier running the 5w30. I seem to lose less oil between changes.

But basically, Mazda themselves says its ok to run both, so if one prefers 0w20 and another prefers 5w30, what's the problem? Different strokes, different folks, both acceptable according to Mazda.
 
My owner's manual states:
USA, Canada, and Puerto Rico: Use SAE 0W-20 engine oil. Except USA, Canada, and Puerto Rico, use SAE 5W-30 engine oil. Mexico: Use SAE 5W-30 engine oil. If SAE 5W-30 engine oil is not available, use SAE 5W-20 engine oil.
Of course, this is for a 2014 Mazda 3 2.5 GT with Skyactive engine. I suggest you go by your owner's manual when deciding which oil to use.
 
AFAIK, the minimum base oil quality is higher for 0W-20 than it is for 5W-20. Like, you can make a semi-synthetic 5W-20, but a 0W-20 has to be fully synthetic (by the industry's generally accepted definitions). So, it's not a given that 5W-20 will hold up better in high temps. Depending on the oils in question, the 5W-20 could well be worse.

Minor differences in these engines, though. Very few of us will ever see the kinds of conditions in which those differences would matter – or own our cars long enough to see the results pan out. And either way, engine oil generally doesn't make a noticeable difference over the life of the vehicle unless it's far out of spec in some way. The main factors are

1. How the engine was designed;
2. How it was made; and
3. How well it's running (fuel quality, state of maintenance, etc.)

roughly in that order.

FWIW.
 
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For anyone still under powertrain warranty, you should probably stick with the recommend
0W-20(in US/Canada) for several reasons:
New engine,
Design specs/tight clearances
Warranty

After the powertrain warranty has expired and after approx. 130,000 miles, I could see switching out to 5W-20(preferably) or maybe even 5W-30 as the older engine is worn, (worn bearings, wider clearances, etc.). I may switch to a 5W-20 after the warranty period.
 
Some BITOGer might suggest that the 0w20 has better base stock and that is why Mazda stamp on my oil fill cap is 0w20 and I believe that. Ed
 
Really? Care to expand on that? How are they different? I'd also be curious to know the difference between the N/A engine and the turbo version, besides the turbo. They are both the 2.5 engines, and if they have the same internals, why is it OK for one to use 5w30 dino oil (turbo), while the other says to use 0w20?
I'm not trying to be a smart Alec here. I genuinely want to know the differences, if there are any.
YES their is a difference. I recalled before purchasing my 2016 2.0L CX3 I read that the European versions had 14:1 compression and the N.A. version had 13:1 compression.

I also recall reading that thinner oil goes through less heat stress since it flows faster though the engine and providing better cooling too. Cold starts cause the most wear to an engine so getting oil flowing quickly with 0W20 will reduce wear at start-up. Unless you are taking the car to the track I see no need for 5W30 on these engines any time of the year.
 
My '15 is still young at only 72k miles but no noticeable oil consumption just using the 0W-20 Mazda moly... just gonna stay the course with that.
 
Well, I switched out to 5w30 last week, and then took a four hour trip to Syracuse for a few days. Car ran nice and smooth and quiet both ways.
I can't say I notice a real difference just driving around town, but I do notice a difference on cold starts. It's quieter for sure.
As for warranty fears, the last time I used 30 weight oil, it was done at the dealer. They had no problem with it. Besides, if the turbo version can use 5w30, why not the N/A engine?
 
YES their is a difference. I recalled before purchasing my 2016 2.0L CX3 I read that the European versions had 14:1 compression and the N.A. version had 13:1 compression.
That may be true for the 2.0 engine, (I wouldn't know), but is it true for the 2.5 engine?
 
North America also gets different engines than other areas, hence the different requirements.
This earlier statement you made wasn't very specific to be honest.
I took it to mean that North America gets different versions of the same 2.5 Skyactiv engine than other parts of the world. That implies that Mazda makes a different 2.5 engine for North America than say, Australia, Japan or the UK. Somehow I doubt Mazda would go to all that trouble.
 
I'll be switching to 0W-30 after winter. 63K miles on our 2014 CX-5 GT & I noticed the engine is a little louder. Not clattering, just not as quiet. Also it uses 3/4 quarts every 5K miles now so tolerances probably aren't as tight as new. I wouldn't use 0W-30 when new but now it shouldn't be a problem. Especially with our 110 degree Texas summers. I like Amsoil full synthetic.
 
I'll be switching to 0W-30 after winter. 63K miles on our 2014 CX-5 GT & I noticed the engine is a little louder. Not clattering, just not as quiet. Also it uses 3/4 quarts every 5K miles now so tolerances probably aren't as tight as new. I wouldn't use 0W-30 when new but now it shouldn't be a problem. Especially with our 110 degree Texas summers. I like Amsoil full synthetic.
If your 2014 CX-5 GT uses ¾ quart every 5K miles, and the engine is a little louder, the thicker oil could help. But I’d use 5W-30 full synthetic oil like Mazda recommended in addition to 0W-20 oil worldwide (see post #15), especially you’re in Texas.
 
If your 2014 CX-5 GT uses ¾ quart every 5K miles, and the engine is a little louder, the thicker oil could help. But I’d use 5W-30 full synthetic oil like Mazda recommended in addition to 0W-20 oil worldwide (see post #15), especially you’re in Texas.
Agree; It's hot most of the time, and 5W is plenty thin for our NTX climate "cold starts". 5w-30 synthetic in all my vehicles for 20 yrs, except the clapped out Ranger, which runs 20w-50.
 
I know most people won't agree with me but the lower oil viscosities are for the good of the CAFE numbers, not for the good of the engines. Will a 0w-20 get your engine way past your 36,000 warranty period? Absolutely. Gunna see 200,000 ?? Maybe. My brothers 2017 F150 5 liter V8 says 5w-20 on the cap. Not me. I live in a VERY cold place and every vehical I own gets 5w-30 full synthetic every 6000 miles, all 12 months. I own cars/trucks from 1986 to 2022. And they are very happy! :). (Kirkland SP 5w-30 actually). And for the love of God don't use FRAM oil filters. Haha
 
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