So reading around here, people are passionate about their oil, and often recommend Mobil 1 0W/40. It's also quite expensive, probably twice as much as most oil you would put in. So I decided to do a science experiment* that people might find interesting.
I got an oil change at a mechanic that uses Castrol 5W/30. At 3,100 miles, in May, I took a sample and sent it in to Blackstone labs. I replaced the oil with Mobil 1 0W/40 Euro formula. The mechanic used the new/smaller Toyota filter and I used the large one. 3,010 miles later, I sent a sample in to see the difference. I should note I added 1qt of oil shortly before taking the sample because the oil level was at the bottom of the dipstick. I noted this in the Blackstone Labs test, so they should account for it. That also means I spent about $70 on the Mobil 1 oil alone for 3,000 miles.
Here are the results of the first two:
The first column is the Mobil 1 fancy oil. The 3rd column is the Castrol oil.
In the Castrol test they wrote:
"There's very little metal overall in this first sample from your Land Cruiser. Universal averages show typical wear levels for this type of engine after about 4,700 miles on the oil. The shorter run is part of the reason for the lower wear, but that's not taking anything away from the fact that the oil sharing parts here are working well together. If there are any mechanical problems, they aren't obvious here. The oil shows nothing alarming. No coolant or fuel dilution is present and the air and oil filters kept silicon and insolubles very low. Excellent engine and report at 190,856 miles."
In the Mobil 1 test they wrote:
"Thanks for the notes. You can see the difference between this oil and the last at the additives (mostly molybdenum and below). This oil uses more boron and less magnesium than the last, and the other additives are at similar levels. Both oils did a great job, producing a similar amount of wear after using a similar interval. There's no sign of a mechanical problem, and steady wear after a similar run is what we should see from a healthy engine. The viscosity was fine and no fuel or water showed up. Feel free to add another 2,000 miles to this oil. Excellent report!"
So when I got the first results (the control), it already felt a bit silly because that oil did really good anyway. The fancy oil wasn't leagues different. I will probably run this oil for another 2k miles and maybe take another sample. But I didn't take a sample at 5k miles on the original oil so I can't compare them. I am not sure what oil I will use next but maybe the discussion here will help move that along.
*With some disclaimers
- I am not a scientist, but I like science
- I am not an expert on oil
- You would need to do this test on multiple oil changes on multiple trucks to establish an aggregate. This is just one truck and two oil changes.
I got an oil change at a mechanic that uses Castrol 5W/30. At 3,100 miles, in May, I took a sample and sent it in to Blackstone labs. I replaced the oil with Mobil 1 0W/40 Euro formula. The mechanic used the new/smaller Toyota filter and I used the large one. 3,010 miles later, I sent a sample in to see the difference. I should note I added 1qt of oil shortly before taking the sample because the oil level was at the bottom of the dipstick. I noted this in the Blackstone Labs test, so they should account for it. That also means I spent about $70 on the Mobil 1 oil alone for 3,000 miles.
Here are the results of the first two:
The first column is the Mobil 1 fancy oil. The 3rd column is the Castrol oil.
In the Castrol test they wrote:
"There's very little metal overall in this first sample from your Land Cruiser. Universal averages show typical wear levels for this type of engine after about 4,700 miles on the oil. The shorter run is part of the reason for the lower wear, but that's not taking anything away from the fact that the oil sharing parts here are working well together. If there are any mechanical problems, they aren't obvious here. The oil shows nothing alarming. No coolant or fuel dilution is present and the air and oil filters kept silicon and insolubles very low. Excellent engine and report at 190,856 miles."
In the Mobil 1 test they wrote:
"Thanks for the notes. You can see the difference between this oil and the last at the additives (mostly molybdenum and below). This oil uses more boron and less magnesium than the last, and the other additives are at similar levels. Both oils did a great job, producing a similar amount of wear after using a similar interval. There's no sign of a mechanical problem, and steady wear after a similar run is what we should see from a healthy engine. The viscosity was fine and no fuel or water showed up. Feel free to add another 2,000 miles to this oil. Excellent report!"
So when I got the first results (the control), it already felt a bit silly because that oil did really good anyway. The fancy oil wasn't leagues different. I will probably run this oil for another 2k miles and maybe take another sample. But I didn't take a sample at 5k miles on the original oil so I can't compare them. I am not sure what oil I will use next but maybe the discussion here will help move that along.
*With some disclaimers
- I am not a scientist, but I like science
- I am not an expert on oil
- You would need to do this test on multiple oil changes on multiple trucks to establish an aggregate. This is just one truck and two oil changes.