Mazda Moly Oil in 5W-30: Does It Even Exist?

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Occupied Calif.
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2019 CX 5 GT-R
I have not been able to find Mazda Moly oil in 5W-30 weight for my CX 5 turbo. The only thing I can find is the 0W-20 weight or the Mazda branded 5W-30 "Super Premium" which I don't even know what it is. Doesn't say it contains Moly on the label, and I assume it is just a good quality synthetic blend ?
 
Don't know what the 5w30 is but the 0w20 is the only Mazda branded high moly oil.

Just use whatever full synthetic 5w30 you want.
 
I have not been able to find Mazda Moly oil in 5W-30 weight for my CX 5 turbo. The only thing I can find is the 0W-20 weight or the Mazda branded 5W-30 "Super Premium" which I don't even know what it is. Doesn't say it contains Moly on the label, and I assume it is just a good quality synthetic blend ?
No, there's no genuine Mazda 5W-30 full synthetic moly oil available.

Be aware that OEM https://www.amazon.com/dp/ (commissions earned) is totally different from https://www.amazon.com/dp/ (commissions earned). OEM Mazda 5W-30 oil is the same as Castrol GTX which is NOT full synthetic, and it's also a GF-4 oil which is not recommended to use by Mazda. OEM Mazda 0W-20 oil is made by Idemitsu which is full synthetic and a GF-5 oil recommended by Mazda for 2.5L NA engine. There're some gen-2 CX-9 owners got fooled by this and used genuine Mazda 5W-30 oil which is not recommended by Mazda for 2.5T.

Use any major brand 5W-30 full synthetic GF-5 oil should be fine for your 2.5T. If you really want something similar to Mazda moly, https://www.amazon.com/dp/ (commissions earned) should be the best match. It meets the latest Gen-2 Dexos specification and has optimized detergent eliminating LSPI (Low-Speed Pre-Ignition).
 
I'm using Shell Rotella 5w30 now that they have it specifically for gas engines. https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4915464/shell-rotella-gas-truck-oil

Someone on the forum was able to get the technical results


"Shell is a reputable company. I wouldn't dismiss this as a marketing gimmick, even though marketing is always a factor.

Looking at the TDS's, the difference between Pennzoil Platinum (PP) "Gas Automobile" and Shell "Gas Truck" is viscosity and/or viscosity index. Gas Truck 5W-30 has KV100 = 11.7 cSt as opposed to the Gas Automobile (PP) with KV100 = 9.8 cSt.

With the xW-20 viscosities, the difference isn't that obvious but if you look more closely and go ahead and calculate the VI, VI = 166 is less for Gas Truck 0W-20 than Gas Automobile 0W-20 (VI=182) and similarly 156 and 167 for the 5W-20's, meaning less viscosity-index improver (VII) used in the Gas Truck than in the PP.

Therefore, Shell Gas Truck has a thicker oil and/or less VII than PP, which means that the oil film will be thicker with new oil and/or the oil won't shear as much with used oil, resulting in thicker oil film with used oil. Therefore, there is a validity to Shell's claim that the Gas Truck oil will protect the truck engines, which have higher loads, better than regular oil, as the Gas Truck oil is a little thicker and/or doesn't shear as much as their Gas Automobile oil (PP).

Labeling the oil as "all-mileage" is also consistent with this observation, as high-mileage oils tend to be thicker.









You can download the TDS and MSDS from:

http://www.epc.shell.com/

Use the Widman calculator to calculate the viscosity index VI (not provided in TDS):

https://www.widman.biz/Seleccion/calculadores.html

As I posted earlier, the Gas-Truck Oil seems to be thicker (higher KV100) and/or more shear-stable (lower VI) than Pennzoil Platinum. Thicker oil (or more shear-stable, so remains thick during OCI) is consistent with the marketing claims that:

"... particularly gasoline pick-ups and SUVs that tend to experience more extreme conditions including driving with heavy load (oil-film squeezing), driving in dusty conditions (need thicker oil film to surround the dust particles), stop and go driving (oil-film squeezing during takeoffs), frequent short trips (oil thinning due to fuel dilution), extreme hot or cold temperatures (oil thinning in extremely hot weather), and extensive idling (oil thinning and/or oil-film squeezing in hot and low-RPM conditions)."

According to the recommendation flowchart, it's not recommended for automobiles -- that's probably because the fuel economy will be a little less due to thicker oil, albeit still within the ILSAC GF-5 test limits.
"
 
I guess Castrol Edge 5W-30 should serve me well then. It is a full synthetic, rated GF5 and SN+, meets DEXOS requirements, and is designed for Gas Direct Injection turbo engines. I wish it were higher in Moly like my previous favorite Redline 5W-30 but you can get the Castrol for about $23/5 quarts as opposed to $65 for 5 quarts of Redline.
 
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I guess Castrol Edge 5W-30 should serve me well then. It is a full synthetic, rated GF5 and SN+, meets DEXOS requirements, and is designed for Gas Direct Injection turbo engines. I wish it were higher in Moly like my previous favorite Redline 5W-30 but you can get the Castrol for about $23/5 quarts as opposed to $65 for 5 quarts of Redline.

It's good oil. Have had plenty of good UOA's using Castrol Edge 0w20 on my Gen 1.
 
OEM Mazda 5W-30 oil is the same as Castrol GTX which is NOT full synthetic, and it's also a GF-4 oil which is not recommended to use by Mazda.

Castrol GTX is GF-5 approved.
So either Mazda 5w-30 isn't re-bottled GTX or your Amazon source hasn't been updated. You'd be hard pressed to find a manufacturer require or recommend a certain approval/certification and not offer an OEM option.
 
Castrol GTX is GF-5 approved.
So either Mazda 5w-30 isn't re-bottled GTX or your Amazon source hasn't been updated. You'd be hard pressed to find a manufacturer require or recommend a certain approval/certification and not offer an OEM option.
Theres a discussion in CX-9 forum 3 years ago when people with new 2.5T went to Mazda dealer changing oil and dealer used OEM Genuine Mazda 5W-30 Super Premium Oil P/N: 0000-77-5W30-QT. Later they found the oil doesnt meet the requirement and its actually a Castrol GTX. Yeah its hard to believe Mazda sells OEM 5W-30 oil doesnt meet recommendation. But thats the fact and I believe those Mazda OEM 5W-30 oil has been there long before 2.5T came out. The specs are out of date like Castrol GTX for modern engines.

Castrol GTX is a conventional oil which is different from Castrol GTX Ultraclean you linked which is a synthetic blend. Therere Castrol GTX Magnatec and Castrol GTX High Mileage which are also different from good old Castrol GTX.

My 1998 Honda CR-V with 187,153 miles is using Castrol GTX 5W-30 since new, definitely a good oil.
 
Yes, I am aware that I posted the Ultraclean variant as the traditional GTX formula (in 5w-30) seems to be missing from Castrol*s site. Including the link you provided. From the link, the closest to 5w-30 is 10w-30, which is approved GF-5.

What recommendation are you referring to that the Mazda oil doesn*t meet? I just pulled up the manual for the 2.5T and the only thing it mentions as far as specs go are SM or SN API approval or ILSAC approval. Nowhere (that I found) does it specify GF-5.

I agree with you, GTX is a fine oil, have some sitting on the shelf myself. Just not sure where you*re getting this requirement and supplier information.
 
No, there's no genuine Mazda 5W-30 full synthetic moly oil available. Use any major brand 5W-30 full synthetic GF-5 oil should be fine for your 2.5T. If you really want something similar to Mazda moly, https://www.amazon.com/dp/ (commissions earned) should be the best match. It meets the latest Gen-2 Dexos specification and has optimized detergent eliminating LSPI (Low-Speed Pre-Ignition).

Mine doesn't have enough miles for an oil change yet but plan to use either Zepro or Liqui-Moly Molygen. It appears the Molygen is close to what the OP is looking for.

https://www.amazon.com/dp/ (commissions earned)

https://www.liqui-moly.us/en/products/molygen.html
 
Yes, I am aware that I posted the Ultraclean variant as the traditional GTX formula (in 5w-30) seems to be missing from Castrol*s site. Including the link you provided. From the link, the closest to 5w-30 is 10w-30, which is approved GF-5.

What recommendation are you referring to that the Mazda oil doesn*t meet? I just pulled up the manual for the 2.5T and the only thing it mentions as far as specs go are SM or SN API approval or ILSAC approval. Nowhere (that I found) does it specify GF-5.

I agree with you, GTX is a fine oil, have some sitting on the shelf myself. Just not sure where you*re getting this requirement and supplier information.
Apparently Castrol is phasing out its GTX conventional oil, hence some popular viscosity such as 5W-30 for older cars are no longer available although I still have more than 2 cases of Castrol GTX 5W-30 for my CR-V.

I agree that Mazda says very little in our owner's manual for oil spec requirements. The key to me is a turbo engine should use full synthetic oil. Those failed to use full synthetic oil in earlier days on VW/Audi's 1.8T had learned the lesson, so as the VWoA who got sued for oil sludge issue on its turbo engine.

Genuine Mazda SAE 5W-30 Super Premium Motor Oil (P/N: 0000-77-5W30-QT) definitely is a GF-4 conventional (not full synthetic) oil as the picture showed. The label doesn't lie.
 
Apparently Castrol is phasing out its GTX conventional oil, hence some popular viscosity such as 5W-30 for older cars are no longer available although I still have more than 2 cases of Castrol GTX 5W-30 for my CR-V.

I agree that Mazda says very little in our owner's manual for oil spec requirements. The key to me is a turbo engine should use full synthetic oil. Those failed to use full synthetic oil in earlier days on VW/Audi's 1.8T had learned the lesson, so as the VWoA who got sued for oil sludge issue on its turbo engine.

Genuine Mazda SAE 5W-30 Super Premium Motor Oil (P/N: 0000-77-5W30-QT) definitely is a GF-4 conventional (not full synthetic) oil as the picture showed. The label doesn't lie.

Yup, Castrol started switching up the GTX labels around '16-'17. 5w-30 has been under the Ultraclean moniker since about that time. Hence my confusion to your claim that Mazda 5w-30 is the same oil.

I agree with you that a turbo engine will be better served by synthetic. However, just because this is largely believed doesn't mean that Mazda is issuing the wrong spec for these engines. And if they were originally, it certainly would have been corrected by this time. The specs that Mazda requires are API SM or newer and/or an ILSAC rating. Which ILSAC rating isn't specified. By these parameters, Mazda 5w-30 absolutely meets the requirements created by the manufacturer. So to say that individuals using Mazda 5w-30 are using an oil that doesn't meet the vehicles requirements is factually incorrect.

Mazda isn't the only manufacturer requiring conventional oil in their turbos. Hyundai still specs conventional and Ford (while recommending syn-blend) has a minimum spec that is met with conventional oil. Let's not forget that in the VW case, the reasoning for the sludge was that VW omitted from their manual that a full synthetic was required. 10k mile OCI and conventional oil with a high-revving turbo motor is a recipe for disaster. These manuals were quickly corrected by VW. If this was the case for Mazda, they would be foolish not to correct an error 3 years later.

Given that we haven't seen an exorbitant amount of reporting on excessive consumption or sludge buildup in the 2.5T since its introduction, I think it's fair to say that these motors are adequately protected by conventional 5w-30 with an SM or newer rating as prescribed by Mazda.
 
Yes, I am aware that I posted the Ultraclean variant as the traditional GTX formula (in 5w-30) seems to be missing from Castrol*s site. Including the link you provided. From the link, the closest to 5w-30 is 10w-30, which is approved GF-5.

https://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/C40C97F2F1CE37D680257AA9005313B2/$File/GTX%5FConv%5F2012.pdf

Looks like 5W-30 is GF-5
 
CASTROL used to be the oil that Mazda recommended. Is it still? I am debaiting on using 5w30 Pennzoil Plat or Castrol EDGE in my new CX5 turbo. Any thoughts on that?
 
CASTROL used to be the oil that Mazda recommended. Is it still? I am debaiting on using 5w30 Pennzoil Plat or Castrol EDGE in my new CX5 turbo. Any thoughts on that?
For 2021 CX-5, Mazda doesn’t say Castrol® as one of the recommended engine oils in owner’s manual like it used to be. Between the 2 oils you listed, I personally prefer Castrol Edge 5W-30 full synthetic oil.

Here’s oil recommendation on 2021 CX-5 2.5T for USA and Canada:

A38BA5B3-2E15-4292-89B2-95A404BCB32C.jpeg

3A3C3701-4003-4BF6-BBD1-9B8F52DC1166.jpeg


And here’s oil recommendation on 2021 CX-5 2.5T for areas other than USA and Canada:

D93D491D-2E8A-4A7D-BD36-F1A07F7A4FE9.jpeg



But I agree with dunhillmc. If I had a 2.5T, Idemitsu SP / GF-6 5W-30 oil would be my top choice.
I recommend the Idemitsu 5w-30. Idemitsu makes (made?) the Mazda high moly 0w-20

71Yf-H2guNL._AC_SL1500_.jpg
The best part of this oil is it meets or exceeds the latest SP / GF-6 standard.

It claims the following improvements over GF-6:
  • 30% more protection against engine wear
  • 26-46% reduction in oil consumption for longer life
  • Up to 24% improved fuel economy
  • 90% more resistant to viscosity increases
  • Three to four times more protection against cold startups
  • 91% reduction in low-speed pre-ignition (LSPI)
  • 6% cleaner engine
 
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Costco Kirkland signature 5w30 full synthetic is GF6 SP Dexos gen 2 sold as (2) 5 quart jugs in a box for $25 and has a high moly dose as well. Just used it as first change after 2500 miles. Best stuff at crazy cheap price
 
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