I am getting ready to do my first oil change on my 2014 6. The dealer performed the first oil change for free and used bulk synthetic Castrol 0W20. I am now at 10,000 miles and planning to change the oil. My question is this. The only 0W20 that my local Autozone carried was a synthetic Mobil 1 that had a label that stated it was formulated for higher MPG. I have read on other forums where some people are using 5W30 because it is better for the engine in their opinion. I know 0W20 is what Mazda specifies in the US and Canada but they specify 5W-30 in Europe. Why the difference? It seems to me the thicker 5W-30 would be better for the engine. Talk amongst yourselves...
The Great Oil Debate 0W20 v 5W30
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Whenever available, the GF-5 Mazda/Idemitsu Moly 0W20 would be tops on my list. The slippery chock full of molybdenum amount in this syn oil is highly beneficial to the superb fuel economy numbers and low wear/low friction properties for the long stroke 2.5L. Well formulated by Mazda engineers for the Sky-Activ series engines. My fall back/2nd choice, the Mobil 1 Advanced Fuel Economy (AFE) (5qt jug) from my oil stash..
For warranty requirements, I'd play safe and stick to 0W20. Besides, there is no such thing as a GF-5 5W30 Mazda Moly..
For warranty requirements, I'd play safe and stick to 0W20. Besides, there is no such thing as a GF-5 5W30 Mazda Moly..
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Everything he said. There shouldn't be a debate when it comes to brand new cars and manufacturer knows best otherwise they wouldn't bother putting it in the manual.Whenever available, the GF-5 Mazda/Idemitsu Moly 0W20 would be tops on my list. The slippery chock full of molybdemum amount in this syn oil is highly beneficial to the superb fuel economy numbers and low wear/low friction properties for the long stroke 2.5L. Well formulated by Mazda engineers for the Sky-Activ series engines. My fall back/2nd choice, the Mobil 1 Advanced Fuel Economy (AFE) (5qt jug) from my oil stash..
For warranty requirements, I'd stick to 0W20, plus there is no 5W30 Mazda moly..
0W20 moly all the way for me.
I would'nt risk it when it comes to the engine, will go with manufacturer recommendation 0w20. For my first oil change at dealer he even told me to stick with Mazda recommended radiator coolant , that I think is a bit of a stretch, I will use the regular Prestone brand.
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Moly Basics
Molybdenum Disulfide
Molybdenum is a very hard metal with a number of industrial uses.
It is combined with chromium in steel to make the steel harder and more resistant to bending. Most of the bicycle frames produced today use chromium and molybdenum steel. Because the steel is so much harder, the manufacturers can use less, thereby making the frame lighter.
Molybdenum Disulfide (Moly) has been used for decades in lubricating pastes and greases because it is slippery and forms a protective coating on metal parts.
Moly exists as microscopic hexagonal crystal platelets. Several molecules make up one of these platelets. A single molecule of Moly contains two sulfur atoms and one molybdenum atom. Moly platelets are attracted to metal surfaces. This attraction and the force of moving engine parts rubbing across one another provide the necessary thermochemical reaction necessary for Moly to form an overlapping protective coating like armor on all of your engine parts. This protective armor coating has a number of properties that are very beneficial for your engine. The Moly platelets that make up the protective layers on your engine surfaces slide across one another very easily. Instead of metal rubbing against metal, you have Moly platelets moving across one another protecting and lubricating the metal engine parts.
This coating effectively fills in the microscopic pores that cover the surface of all engine parts, making them smoother. This feature is important in providing an effective seal on the combustion chamber. By filling in the craters and pores Moly improves this seal allowing for more efficient combustion and engine performance.
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This overlapping coating of Moly also gives protection against loading (perpendicular) forces. These forces occur on the bearings, and lifters. The high pressures that occur between these moving parts tend to squeeze normal lubricants out.
Eventually, there is metal to metal contact, which damages these moving parts and creates large amounts of heat. Fortunately, this is not the case with some lubricants.The layer of moly that forms on these moving surfaces can withstand pressures of 500,000 psi, without being squeezed out.
Engineers and scientists have tried for years to use Moly in motor oils but they had been unsuccessful because they could not find a way to keep Moly in suspension. Once Moly was put into suspension it would gradually settle out. It was easy to see it come out of suspension because a black sludge would collect on the bottom of the oil containers. In engines it would settle to the bottom of the crankcase or clog oil pathways and filters.
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Engineers have overcome these obstacles. They have developed a process that keeps Moly in suspension and isn’t filtered out. Since that time theproduct has undergone extensive independent testing in labs and in the field for many years to insure that the product stands up to the rigorous needs of today’s engines. With the plating action of Moly reducing friction which reduces heat, this helps keep rings free from carbon buildup, prevents blow-by, decreases emission, and extends oil life.
Moly Basics - Bob is the Oil Guy
Molybdenum Disulfide
Molybdenum is a very hard metal with a number of industrial uses.
It is combined with chromium in steel to make the steel harder and more resistant to bending. Most of the bicycle frames produced today use chromium and molybdenum steel. Because the steel is so much harder, the manufacturers can use less, thereby making the frame lighter.
Molybdenum Disulfide (Moly) has been used for decades in lubricating pastes and greases because it is slippery and forms a protective coating on metal parts.
Moly exists as microscopic hexagonal crystal platelets. Several molecules make up one of these platelets. A single molecule of Moly contains two sulfur atoms and one molybdenum atom. Moly platelets are attracted to metal surfaces. This attraction and the force of moving engine parts rubbing across one another provide the necessary thermochemical reaction necessary for Moly to form an overlapping protective coating like armor on all of your engine parts. This protective armor coating has a number of properties that are very beneficial for your engine. The Moly platelets that make up the protective layers on your engine surfaces slide across one another very easily. Instead of metal rubbing against metal, you have Moly platelets moving across one another protecting and lubricating the metal engine parts.
This coating effectively fills in the microscopic pores that cover the surface of all engine parts, making them smoother. This feature is important in providing an effective seal on the combustion chamber. By filling in the craters and pores Moly improves this seal allowing for more efficient combustion and engine performance.
This overlapping coating of Moly also gives protection against loading (perpendicular) forces. These forces occur on the bearings, and lifters. The high pressures that occur between these moving parts tend to squeeze normal lubricants out.
Eventually, there is metal to metal contact, which damages these moving parts and creates large amounts of heat. Fortunately, this is not the case with some lubricants.The layer of moly that forms on these moving surfaces can withstand pressures of 500,000 psi, without being squeezed out.
Engineers and scientists have tried for years to use Moly in motor oils but they had been unsuccessful because they could not find a way to keep Moly in suspension. Once Moly was put into suspension it would gradually settle out. It was easy to see it come out of suspension because a black sludge would collect on the bottom of the oil containers. In engines it would settle to the bottom of the crankcase or clog oil pathways and filters.
Engineers have overcome these obstacles. They have developed a process that keeps Moly in suspension and isn’t filtered out. Since that time theproduct has undergone extensive independent testing in labs and in the field for many years to insure that the product stands up to the rigorous needs of today’s engines. With the plating action of Moly reducing friction which reduces heat, this helps keep rings free from carbon buildup, prevents blow-by, decreases emission, and extends oil life.
Moly Basics - Bob is the Oil Guy
AutoZone is slipping then. In my local Walmart they now have like six different 0W20s:
Valvoline
Quaker State
Mobil 1
Castrol Edge
Pennzoil Platinum
Supertech
and others will follow soon
In my humble opinion, unless there is something very different about Mazda's skyactive engine, all of these are pretty much equal. Just buy whatever you like the most. I just got QSUD 0W20 for our Prius because Quaker State will send you $20 rebate if you sign up for their "warranty" program. Free oil is always good, QSUD is basically like PP, at least they come from the same parent company and VOAs look very similar. Every once in a while NAPA also has a good sale of NAPA Synthetic (and that's basically a Valvoline synthetic)
Valvoline
Quaker State
Mobil 1
Castrol Edge
Pennzoil Platinum
Supertech
and others will follow soon
In my humble opinion, unless there is something very different about Mazda's skyactive engine, all of these are pretty much equal. Just buy whatever you like the most. I just got QSUD 0W20 for our Prius because Quaker State will send you $20 rebate if you sign up for their "warranty" program. Free oil is always good, QSUD is basically like PP, at least they come from the same parent company and VOAs look very similar. Every once in a while NAPA also has a good sale of NAPA Synthetic (and that's basically a Valvoline synthetic)
A lot of guys on Bob is the oil guy will disagree regarding Moly being required as a signal for high quality oil. For one, there are anti-wear additives that work just as well. For example, sodium-based Valvoline turns out pretty good UOAs. Next, you don't always know if the Molybdenum additives comes in the more sophisticated tri-nuclear form or not.
There was always a long debate about 0W20 vs 5W30 and I don't think this issue has ever been settled. In any case, I don't think there has ever been a hard proof of thinner oil being worse for the engines, specially when its recommended. Don't forget that the 5W30s when they're recommended, are often recommended in non-synthetic form. By the time the 5W30 is out of the pan, it can shear down to 20 grade anyways. A synthetic 0W20 should be shear stable and stay within its viscosity grade longer. As engines are redesigned, tolerances decrease and in that case the thinner oil should actually protect better.
There was always a long debate about 0W20 vs 5W30 and I don't think this issue has ever been settled. In any case, I don't think there has ever been a hard proof of thinner oil being worse for the engines, specially when its recommended. Don't forget that the 5W30s when they're recommended, are often recommended in non-synthetic form. By the time the 5W30 is out of the pan, it can shear down to 20 grade anyways. A synthetic 0W20 should be shear stable and stay within its viscosity grade longer. As engines are redesigned, tolerances decrease and in that case the thinner oil should actually protect better.
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My driving habits calls for 5k+ miles/6mos of mostly 65%/35% fwy/city driving. So it's just about right (below 7,500mi) for a 6 month dealer OCI to keep warranty things in effect. I'd bring my own syn oil of choice every time I pull into my dealership for OCI service...and I'd keep things safe and my M6 car life simple (and I'm not about to pull hairs on Moly and being anal, tri-nuclearama-jig or not). As much as I am big on thick oils for years (and still am with a stash full; had a 1.8T German, fed on a variety of xW30-xW40 syn oil with a Mannolator filter)...I'd stick to 0W20 (Mobil 1 AFE, good..Mazda/Idemitsu Moly, the better!) for the M6, while on American soil.
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That's just the thing - there IS something, well a LOT of things, different with the Skyactive engines. Sure, they'll be just fine without the Moly, but with all the new lightweight parts and precision and quality of each piece, wouldn't you want to do anything possible to keep it running as well as possible? Even if moly doesn't do anything, tough to say, but it costs no more than your conventional oil and lasts just as long - I say why bother with anything else.
Just like Shell gasoline with the nitrogen - that's been proven to help engines but costs no more than normal gas - I make it a point to get shell any time I can because what's driving an extra mile for gas if it helps my engine go another 5000?
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Living in Texas...ie where temps are HOT (100F+), I'm a bit leery of running such a thin oil. Especially since Mazda recommends using 5w-30 for Mexico. Well, I'm basically living in Mexico as far as climate goes. BUT, I don't want to void a warranty by not using the correct oil for USA.
BUT, since the 0W-20 oil from Mazda (made by IDEMITZU in Japan) has so much MOLY in it....I'm going to not second guess the Mazda engineers.
I wouldn't trust any other brand 0w-20 for the SKYACTIV engine. But I do tend to be a bit brand loyal...ie OEM oil filters, etc.
Interesting thing is the local Mazda dealership isn't using this Mazda brand 0w-20. They are using Castrol Syntec 0w-20. When I asked for the Mazda oil with Moly, they looked at me strange. They then looked up the part number...."Ahh, we'll have to order that."
I do all my maintenance anyway... so Mazda 0w-20 w/ MOLY, and OEM filters for me.
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BUT, since the 0W-20 oil from Mazda (made by IDEMITZU in Japan) has so much MOLY in it....I'm going to not second guess the Mazda engineers.
I wouldn't trust any other brand 0w-20 for the SKYACTIV engine. But I do tend to be a bit brand loyal...ie OEM oil filters, etc.
Interesting thing is the local Mazda dealership isn't using this Mazda brand 0w-20. They are using Castrol Syntec 0w-20. When I asked for the Mazda oil with Moly, they looked at me strange. They then looked up the part number...."Ahh, we'll have to order that."
I do all my maintenance anyway... so Mazda 0w-20 w/ MOLY, and OEM filters for me.
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I typically go with Mobil, but I may try Shell (only reason I haven't is the Mobil station is way closer).
Kodo - thanks for the info. I will reach out to my own dealership about what oil they use.
UPDATE - just talked to my dealership (CJ Wilson Mazda) - they use GF-5 w/Moly for oil changes. Yay.
So I just did the oil change and went with factory filter and Mobil 1 0W20 AFE that I got at Wal-Mart for $25 for a 5Qt. jug.
After the oil change I also applied Armor All to the plastic fairing. I think I may need to be tested for OCD lol...
After the oil change I also applied Armor All to the plastic fairing. I think I may need to be tested for OCD lol...
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My dealer used Valvoline Synpower 0W30 for my oil change. Don't know it has moly in it or not. I also only use Shell gas in my 6.
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What's the cost per quart? ThanksLiving in Texas...ie where temps are HOT (100F+), I'm a bit leery of running such a thin oil. Especially since Mazda recommends using 5w-30 for Mexico. Well, I'm basically living in Mexico as far as climate goes. BUT, I don't want to void a warranty by not using the correct oil for USA.
BUT, since the 0W-20 oil from Mazda (made by IDEMITZU in Japan) has so much MOLY in it....I'm going to not second guess the Mazda engineers.
I wouldn't trust any other brand 0w-20 for the SKYACTIV engine. But I do tend to be a bit brand loyal...ie OEM oil filters, etc.
Interesting thing is the local Mazda dealership isn't using this Mazda brand 0w-20. They are using Castrol Syntec 0w-20. When I asked for the Mazda oil with Moly, they looked at me strange. They then looked up the part number...."Ahh, we'll have to order that."
I do all my maintenance anyway... so Mazda 0w-20 w/ MOLY, and OEM filters for me.
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I've been getting mine locally in Baltimore for $6.85/qt, no shipping, but 6% state tax. I'm no stranger to high dollar oils (my G37x likes Motul X-Max 5W-30). The highest dollar 0W-20 is Eneos Sustina (about $10/quart if not $12), and extra moly or not, I beg to think that it's higher quality oil than the Mazda branded Idemitsu, which is no slouch in its own right. Sustina uses a proprietary polymer that encapsulates dirt in an effort to minimize sludging. Boutique oils all have some angle, whether it be base stock (4 or 5) and/or proprietary polymer additives.
Contrary to popular opinion, and flame if you must, Mobil 1 is not even on par to Pennzoil Ultra at any given viscocity.
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Sustina (con Moly) can be had from NAPA. It is premium indeed over the Mazda Moly. But for practical reasons, for me...the Mazda is pretty good enough for the M6.
That Mazda Moly with your state tax is but a penny less where I will get mine net, ($6.19/qt + shipping) for a case to my door. 2 cases would lower the price/qt even more, good for 2yrs worth of dealer changes. My car is due for the 1st OCI by mid Nov. I'd likely pull the trigger for 2 cases of the Mazda Moly by Thurs...
Btw, I have 12ltrs of Grp V Motul 0w40 8100 Ester E-Tech from my oil stash..too bad I can't use it. Way thick for the "watery" 0W20 needs for the Sky-G.
The Motul Ester E-Tech is what I used in my '99 MB E320 4-Matic right up until it was totaled in 2008. That sucker had an 8.5 qt. crankcase, and required synthetic, as one would guess by the viscocity rating. It's formulated primarily for European gasoline engined vehicles.
ExB5, would you mind revealing your internet source for the $6.19 Mazda 0W-20 with Moly? It may be worth doing a 2 case deal, even though I have 16 quarts of the stuff on hand currently.
I've stockpiled oil in the past for a particular car only to have the car totaled, so I try not to get carried away unless the deal is hard to pass up.
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Sorry, I meant $6.29/qt...not $6.19. Typo.
It's from Partsvp.com. The lowest I've found anywhere.
$6.29 (Part # 0000G50W20MQ) Mazda GF-5 0W20 W/MOLY (QR
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