Hi everyone,

Back in April I posted my Blackstone Lab oil analysis report and stated my intent to get the same analysis for different brands of oil as a non-scientific experiment to see what brands seemed to perform better between Mobil 1 0W-20 and Toyota Synthetic 0W-20. Before I get any questions as to why I chose these two brands to compare the answer is that it was an accident. I purchased my LS460 from a Cadillac dealership back in September of 2014. I have no idea what brand of 0W-20 oil the dealership used but I assumed it wasn't anything particularly "high-end". After about 5k miles I changed the oil to Mobil 1 0W-20 and got a Blackstone analysis done on the dealership oil. Right after I changed to Mobil 1 I read through a lot of posts here and decided I would move to Toyota 0W-20 at my next oil change. Well, I just did that oil change after about 6k and switched to Toyota synthetic. I got a Blackstone analysis done on the Mobil 1 oil I just drained and the results are in. Eventually, when it is time for my next oil change I will have an analysis done on the Toyota oil so I can compare results on all three oils.

Attached to this post are the two oil analysis reports. There is the initial report on the unknown dealership oil and the second report on the Mobil 1 oil. My driving habits across both oils has remained the same (i.e., roughly the same mix of highway versus city driving, same speed/acceleration habits, no new major roadtrips).

The bottom line is that, to no surprise, my analysis results on Mobil 1 were significantly better. While Blackstone recommended I stay at a 5k mile oil change interval on the unknown dealership oil, they recommend I can push it to 8k miles on the Mobil 1 oil. It will be very interesting to see what the results will be for the Toyota oil.

Hope this is interesting to someone.

 

Great info, thanks for the post

 

Useful information, thank you very much

 

Do I understand correctly that your first sample had 5000 miles on the oil?

 

Thank you for doing this.
Here are some of my observations.

Your first sample seems to be ok in the additive package but it probably wasn't meant for extended drains.
Some of the speculations we have had though our discussions were that this car may not be that hard on oil by design and it's enormous oil capacity, but your sample shows otherwise.

Although Blackstone has given a good report for the Mobil 1 I still think the iron wear numbers are higher then what I would like and it is very typical of some of the other UOA I have seen before with this oil. It's not bad but I have seen better with other oils particularly the Toyota Synthetic.
If your Toyota sample yields half the iron wear it will be conclusive to me that there is strong trend that it's better then Mobil 1.

 

To clarify my question above, do you know that the Cadillac dealer changed the oil just prior to your purchase?

 

I can't be certain exactly when they changed the oil but after I purchased it and checked the dipstick the oil looked relatively clear.

 

I am sure Toyota oil will benefit just by being used after Mobil oil. In my opinion Mobil oil acted as a cleaner.

 

All 0w-20 oil currently is synthetic

 

Well, not quite. There are several semi-synthetics and blends that are available, including Honda, Phillips 66, Kendall and Shell. Others as well.