Mazda 0W-20 moly - 5,370 miles - '15 Mazda CX-5

[Kedis82ZE8]

New member here...

Mazda 0W-20 moly - 5,370 miles - '15 Mazda CX-5 GT AWD with SkyActiv 2.5L

- Regular unleaded 87 octane always used

I’d really like to get the experts opinion here on the UOA I recently had done on my vehicle.. Do you think 10K miles will be possible between changes if these number hold up or is 7500 going to be the limit? Viscosity increase in report?

Current Miles: 22,200 Miles / UOA only performed on oil change at 20,873 miles

- 75% Highway / 25% City

Other than factory fill this vehicle has “only” used the OEM 0W/20 Mazda “Moly” oil referenced in this thread:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2781625

Oil changes at the following mileage: 4,018 miles, 9,491 Miles, 15,503 miles and 20,873 Miles. These intervals were utilized to eliminate any warranty issues as the longest Mazda supports on my model year is 6 months or 7,500 miles between oil changes. Oil changes occurred on a 6 month schedule other than the first oil change which was only about 3 months.

Oil was changed about 1/3 into drain and oil was cold in engine that had not been run since the previous day’s 25 mile highway drive.

- Using Mazda OEM Oil Filter

Thanks!

 

[Kuato]

The oil thickened a bit, and is barely over the 20 weight specification....some might say it is within the sensitivity of the test. Plenty of additive left so IMO 7500 is no problem, and 10k is certainly probable, especially considering your driving patterns.

The question might be how you feel about the warranty, since extending looks like it will put you beyond the recommendations in the OM. In your place I would buy fresh oil and filter every 6 months (saving the receipt) whether you use it or not, and take a sample at 7500 to send in, leaving the oil in, then changing (or taking another sample) based on the UOA.

edit: Didn't mean to make such a run-on sentence....and

 

[WobblyElvis]

Change the oil n filter every six months regardless of mileage. Looks like this wold be around 7,000 miles. Don't bother with a UOA. Save your money. Worry about other things.

 

[Shannow]

It's flashpoint indicates that fuel is an issue, and it's thickening suggests that it's oxidative thickening is outstripping the viscosity loss.

I'm not thinking it's a good idea to go to 10,000...maybe 8 and check via UOA and see which direction it's heading in....or pull it up and 7K and drop the UOA as suggested above

Bear in mind that it was the Japanese OEMs that lobbied to get the TEOST (deposit test) limit raised for 0W20 only, as their high Mo oils can be more deposit forming.

 

[CarbonSteel]

Originally Posted By: Shannow
It's flashpoint indicates that fuel is an issue, and it's thickening suggests that it's oxidative thickening is outstripping the viscosity loss.

I'm not thinking it's a good idea to go to 10,000...maybe 8 and check via UOA and see which direction it's heading in....or pull it up and 7K and drop the UOA as suggested above

Bear in mind that it was the Japanese OEMs that lobbied to get the TEOST (deposit test) limit raised for 0W20 only, as their high Mo oils can be more deposit forming.
I agree; to have thickening and low flashpoint is not an optimum situation. I would UOA again at 7.5-8K and see where it is.

 

[Kedis82ZE8]

Thanks everyone. I appreciate the feedback. Until the powertrain warranty is up I plan to stick with factory change intervals.

 

[DBMaster]

Check out my UOA after 30,000 miles on 0W-20 and microGreen filters. I'm on round 2 now using M1 0W-20 EP.

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3894907/1

 

[HTSS_TR]

Originally Posted By: Shannow
It's flashpoint indicates that fuel is an issue, and it's thickening suggests that it's oxidative thickening is outstripping the viscosity loss.

I'm not thinking it's a good idea to go to 10,000...maybe 8 and check via UOA and see which direction it's heading in....or pull it up and 7K and drop the UOA as suggested above

Bear in mind that it was the Japanese OEMs that lobbied to get the TEOST (deposit test) limit raised for 0W20 only, as their high Mo oils can be more deposit forming.

What is the cause of oxidation ?

We knew that fuel dilution reduces both flashpoint and viscosity(My S2000 2 UOA's). Does full synthetic oil do better job than non-synthetic in oxidation problem ?

Another question, we know that stay in grade is best but which one is worse: thicken or thinning ?

 

[Colt45ws]

The fuel in it even though you say that you run 75% highway makes me wonder why. I wonder if premium fuel in this high compression DI engine would help. If its pumping in more fuel to compensate for lower octane.

 

[Eddie]

Since the wear values are good, I see no issues with the lab values which are VERY close to being within the suggested limits. I wouldn't over think this report as it is a good one. Ed

 

[deven]

Originally Posted By: Eddie
Since the wear values are good, I see no issues with the lab values which are VERY close to being within the suggested limits. I wouldn't over think this report as it is a good one. Ed

+1. Lots of oils will oxidize and then shear later during an OCI. The TBN is 4.5 so you could easily go longer. If fuel or anything else was oxidizing the oil then TBN retention would be compromised too which it clearly is not the case.