Mobil Super Syn 0w20 - 9,829 miles - CX5 w/ 2.5l

[RamFan]

Results aren't as good as the first UOA I did, but it's nothing to be alarmed at. Will be doing another UOA at the next change to get more data. I'm happy with the wear metals decreasing, obviously fuel, flashpoint and viscosity needs improvement. It is to be expected that this UOA would have more fuel though given the colder temps that the car was in during the OCI in question.

OCI history is as follows:

0 - 1,169 - Factory Fill
1,169 - 10,120 - Mag1 0w20
10,120 - 19,949 - Mobil Super Syn 0w20
19,949 - present - Mobil 1 EP 0w20

 

[CapitalTruck]

Fuel contamination ain't no oil issue.

 

[FlyNavyP3]

By comparison I like the Mag1 better. Better TBN retention seemingly. Would definitely trust either for a 10k run. Looking good overall despite slipping out of grade.

 

[Danh]

With a 315 flashpoint and 5.55 viscosity (can't remember seeing a lower 20 weight lab result) there's a lot more that 2.5% fuel dilution. If this analysis was done by Polaris or another gas chromotography lab it would almost certainly fall into the >5% range. But given the prior UOA showed less dilution it's most likely a byproduct of winter/short-tripping driving so the next UOA should be better.

If it were my car I'd shorten the OCI to 5,000 miles: some DI engines are just prone to fuel dilution, Mazda SkyActivs being one of them. Viscosity is a concern here and keep in mind that after a long OCI viscosity will start to increase because of oxidation and, in the case of DI engines, soot. So the viscosity you see in these UOAs may not have been the minimum over the course of the OCI, perhaps explaining the relatively high iron wear numbers.

 

[zeng]

The two oils are holding up well, despite fuel dilution to be tamed .
Am speculating used Mobil Super looks darker gray relatively.
Stouter EP 0W20 appears a good switch.

 

[beanoil]

I would shorten to 5k miles as well. DI's will pollute the oil with fuel.
I had an Equinox that did the same thing. Chevy reflashed the OLM to a more conservative level when I owned it.
Looking at the stats, I'd make a switch back to Mag1. Moly, Boron, Calcium, all at good levels.
It sure looks like all the stuff folks add to their oils is already in Mag1.

 

[edyvw]

Shorten to 5K and use full synthetic oil like Mobil1. Do UOA. If there are still issues with fuel dilution, bring uOA to Mazda and let them check injectors. How is your MPG?
If all is OK, and you still have fuel dilution, switch to 0W30 or 5W30 Mobil1, Castrol Edge, Pennzoil Platinum etc.

 

[tig1]

IS THIS AN EXAMPLE OF TECHNOLOGY GONE IN REVERSE?

 

[4WD]

So you have fuel diluting a 0w20 and these guys recommend 10k OCI - did I read that right ?

 

[edyvw]

Originally Posted By: 4WD
So you have fuel diluting a 0w20 and these guys recommend 10k OCI - did I read that right ?

Sometimes I think Blacsktone is like: Let's see how long we can push it before engine breaks.

 

[Danh]

Originally Posted By: edyvw
Shorten to 5K and use full synthetic oil like Mobil1. Do UOA. If there are still issues with fuel dilution, bring uOA to Mazda and let them check injectors. How is your MPG?
If all is OK, and you still have fuel dilution, switch to 0W30 or 5W30 Mobil1, Castrol Edge, Pennzoil Platinum etc.


If my DI Honda experience is typical, I doubt Mazda will be very helpful. The corporate attitude seems to be:

1) UOAs are of questionable quality and who knows the driving conditions just before taking the sample or if the owner has otherwise messed with the sample
2) We expect fuel dilution and haven't seen a rash of engine problems
3) The OBD system will identify issues with injector leak-down, early thermostat opening, and a variety of other true malfunctions that would cause fuel dilution

The dealer did check fuel trim by cylinder to see if an individual injector was at fault, but after that I was pretty much told to go away unless I had a check-engine light.

Going to a higher viscosity is tempting but there is the warranty to consider. DI does seem like a step backward on this score, at least.

 

[4WD]

7500 miles is not a bad choice either ...

 

[Ohle_Manezzini]

Those gdi engine run so rich, I'd run E85 on them, seriously!

 

[Artem]

Are you going by the maintenance reminder for the OCI? My 2014 Mazda 3 has the option to go by a preset mileage of your choice or let the ECU decide when to change the oil based on driving conditions.

I noticed I'm usually at 60% after 3-4K miles of use. I run Premium fuel in mine (it's been dyno tuned to take advance of 93 octane) and I have no fuel dilution.

 

[RamFan]

Originally Posted By: edyvw
Shorten to 5K and use full synthetic oil like Mobil1. Do UOA. If there are still issues with fuel dilution, bring uOA to Mazda and let them check injectors. How is your MPG?
If all is OK, and you still have fuel dilution, switch to 0W30 or 5W30 Mobil1, Castrol Edge, Pennzoil Platinum etc.


All is well with fuel economy currently at a lifetime average of 26.4 mpg. While under warranty I won't be switching to a 30 weight.

Originally Posted By: edyvw
Originally Posted By: 4WD
So you have fuel diluting a 0w20 and these guys recommend 10k OCI - did I read that right ?

Sometimes I think Blacsktone is like: Let's see how long we can push it before engine breaks.


The idea is to see what numbers if any change to start tracking a possible problem. Automatically shortening would add a variable which can complicate diagnosis, if there's any to be made.

Originally Posted By: Artem
Are you going by the maintenance reminder for the OCI? My 2014 Mazda 3 has the option to go by a preset mileage of your choice or let the ECU decide when to change the oil based on driving conditions.

I noticed I'm usually at 60% after 3-4K miles of use. I run Premium fuel in mine (it's been dyno tuned to take advance of 93 octane) and I have no fuel dilution.


I am going by the OLM. This showed 50% left. UOA #1 showed 60% left. Manual states to change at 0% or 1 year/10k miles, which ever comes first when using the OLM feature. You can also stick to a "regular" OCI as well but I want to try the OLM (so far it seems mighty optimistic) I'm going to run this the same length and see what the results are. If they're the same I'll reduce to 8k mile OCI and re-sample.

 

[CT8]

Originally Posted By: tig1
IS THIS AN EXAMPLE OF TECHNOLOGY GONE IN REVERSE?
Remember when the Fuel injection entered the market it had its problems. give the tech another 5 years + to get it working properly or to prove its merits. I really like the Bosch CIS[non electric] myself.

 

[bigt61]

IMO - the early switch from FF didn't help the oil ring break-in - that's why you have dilution. I'd run some semi-synthetic for a few oil changes - follow the OLM & Keep it topped off. Then go back to full synthetic.

 

[ChrisD46]

+1 unless highway milage only any DI engine I would own gets a 5K mile OCI max plus I would consider going up a grade (0W30 M1 AFE). As for going back to a semi - synthetic , I question if that has anything to do with rings being seated in a DI engine as that was done already before you got the vehicle from the factory , moving the car around the lot(s) , etc. Akso , why do some new cars come from the factory with synthetic to begin with if ring seating was a concern / problem ?
Originally Posted By: edyvw
Shorten to 5K and use full synthetic oil like Mobil1. Do UOA. If there are still issues with fuel dilution, bring uOA to Mazda and let them check injectors. How is your MPG?
If all is OK, and you still have fuel dilution, switch to 0W30 or 5W30 Mobil1, Castrol Edge, Pennzoil Platinum etc.

 

[PimTac]

I agree with ChrisD46. Go with a 5k oci unless you are driving highway mostly, then 7500 might be doable. The fuel dilution in DI engines is the big factor.

 

[CaspianM]

Originally Posted By: bigt61
IMO - the early switch from FF didn't help the oil ring break-in - that's why you have dilution. I'd run some semi-synthetic for a few oil changes - follow the OLM & Keep it topped off. Then go back to full synthetic.

Early oil change is not really meant to break-in the compression rings. Rings would break-in by the time engine has less than 50 miles on it regardless of oil change. Or it is completely missed by then.
This kind of fuel dilution is usually as a result of improper warm up/too much idling before sampling.