Turns out all of the Mobil 1, 5w20, and 3,000 mile oil change haters can suck [it] this data.
Received my latest oil analysis results back from Blackstone Labs for my 2010 3.8 Coupe with about 170k total miles on the vehicle (as of tonight) and 11,076 miles on the oil. I ran this oil sample hard and long. Harder and longer than I ever have before and got some good results. I used off the shelf Mobil 1 Extended Performance 5w20 with a Purolator PureOne filter and added a magnetic drain plug for kicks and giggles. I Live in Texas so it sees plenty of 100+ degree temperatures. Every time my engine is warmed up it has a wide open throttle pull to the redline. A vast majority of my driving is on the interstate at ~80mph, and probably 2,000-2,500 of the 11,076 miles on the oil sample was from sustained 100+mph cruising on the toll roads with the A/C blasting on high. Aka I wasn't easy on the oil at all. After getting positive results back from the last 10,222 mile analysis the guys at the lab suggested I could take it longer to up to 12,000 miles. I changed it slightly early at 11,076 just because I had time off of work.
The universal averages on the right hand side of the report are set at an average of a 6,400 mile oil change interval. The aluminum particle count of 11ppm is only 3ppm higher than the 8ppm average from a 6,400 mile sample, or wearing about 1ppm/1,000 miles as opposed to 1ppm/800 miles from the average sample...meaning I'm still wearing less aluminum from the engine per mile than average even with the extended drain interval and loads the engine sees. The iron particle count of 26ppm, though it is 10ppm higher than the universal average is still wearing better than normal considering the interval given, wearing at 1ppm/426 miles vs the universal average of 1ppm/400 miles. All other wear metals seem quite stable regardless of the interval driven. Viscosity is still within grade for a 5w20 showing that it can handle the stress. Flashpoint is still good, fuel content was under 0.5%, water and antifreeze were not present and the insolubles (soot) count was steady at 0.3% again. TBN (total base number) aka the amount of active additive remaining was still above a 1.0 so it could safely go longer. It is worth noting that this sample (Mobil 1 Extended Performance 5w20) was run an almost identical mileage to the 11,037 mile sample (Pennzoil Ultra) from 9/5/15 and had better numbers in just about every category. This is enough for me to conclude that Pennzoil Ultra may not be the best oil for the 3.8 engines compared to the Mobil 1 E.P.
I am currently running the new Mobil 1 Annual Protection 5w20 oil that they claim is good for 1 year or 20,000 miles with the Purolator PureOne filter. I will probably take a sample around the 12,000 mile mark this time to see how it holds up compared to their Extended Performance line of oils, and pending results of the sample I will alter the next oil change interval appropriately. The engine runs extremely smooth and quiet without any start up noises or knocks as well. She's perfectly happy and healthy, and ready for the next 12,000 miles.
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