ï»¿Mobil Delvac 1 ESP 5w-40, 8k miles, 07 gas 6.2 I do extended oil changes and used oil analysis is so WE HERE ON THIS FORUM might learn something, and I find it interesting. I'm also trying to figure out how long I can/should go between oil & filter changes with our now 147k mile new to us 2007 Yukon Denali w/all aluminum 6.2L . The main tool I use to determine OCI are UOA reports. I've been doing UOA for 10 yrs on various vehicles. I mainly use Oil Analyzers Inc, but I have used Blackstone and JB Services too. Here's a link to one of our vehicles that I've had for 10+ yrs and have done 10 UOA : https:/
We bought this old Yukon Oct. 2018 w/130k miles off a used car lot without any mx history. I figured out real quick that it burned and leaked a lot of oil. But, it had good oil pressure and drove like a dream. I am a DIYer. I fixed the leaks by changing the rear main seal and oil pan gasket. I cured the oil burning by installing the new improved driver side valve cover and performing TSB 10-06-01-008M. There is a lot of gunk/crud built up inside the engine from its prior life. When I had things apart I cleaned everything as best I could.
I always cut open the old oil filters to see what's what. Each time I find black carbon/gunk/crud at the bottom of the pleats. I've asked myself "are my oil change intervals are causing this stuff??, or is the Mobil Delvac 1 ESP 5w-40 actually slowly cleaning up the carbon/gunk/crud that's stuck on the guts of the engine from it's prior life?" I think I have my answer. The oil is cleaning things up a little. I came to this conclusion by taking off the new improved driver side valve cover for inspection that I put on when I fixed everything 16,000 miles ago and started using this oil. The valve cover is as clean new inside and out.
I installed a catch can in the PVC system, and installed a remote engine oil bypass filtration system that utilizies a remote Amsoil EaBP90 spin-on filter. Now the sump capacity is 6+ qts. Before I fixed everything, the catch can was catching about 1oz of oil every 100 miles. Now it catches 1 oz every 6000 miles. The engine now uses <1/2 qt of oil between changes(no make-up oil).
Here are the first two UOA results from Oil Analyzers Inc(OAI-Polaris Labs). The oil in both reports is Mobil Delvac 1 ESP 5-40w. This oil is dual rated for both spark(gasoline) and compression(diesel).
https:/ www.bobistheoilguy.com/ foru...-14-500-miles-toy-fj-cruiser-4-0l#Post4918507 /
We use this vehicle mostly for hwy driving(70%). It sees the hot TX 100 degree summers and the cold CO -20 degree mtn winters. The oil filter for the first run was NAPA 47060 Platinum, and the 2nd a Fram XG10575. I don't change the oil and filter when I take a sample. I wait to see the results, then I make that decision. I did immediately change it when I read the first report, but went another 1800 miles after the second report, then changed to Mobil Delvac 1 ESP 5w-30.
OIL-Mobil Delvac 1 ESP 5w-40
no make-up oil
www.mobil.com/ English-US/ Commercial-Vehicle-Lube/ pds/ GLXXMobil-Delvac-1-ESP-5W40
ï»¿The Labs comments for the first report are: ï»¿LUBRICANT CHANGE is suggested. OXIDATION is at a SEVERE level. OCI may be over extended or unit may be running too hot. Base # is MODERATELY LOW. Silicon is at a MODERATE LEVEL. Please submit a new virgin sample of this oil for our BASELINE REFERENCE. ï»¿The Labs comments for the second report are: ï»¿Please submit a new virgin sample of this oil for our BASELINE REFERENCE. Oxidation is flagged, however we cannot determine the severity of this oxidation value. When using synthetic oil starting oxidation values are typically higher. Continue to monitor other fluid properties for trends of oil degradation. We Love This Yukon
MILES IN USE 8.1k 6.2k MILES 140.7k 147.0k SAMPLE TAKEN 3/24/19 7/24/19 ï»¿Wear Metals (ppm) ALUMINUM 6 4 CHROMIUM 1 1 IRON 39 40 COPPER 10 8 LEAD 9 5 TIN 0 0 NICKEL 0 1 SILVER 0 0 ï»¿Contaminant Metals (ppm) SILICON 31 18 Sodium 31 16 Potassium 3 0 ï»¿Multi-Source Metals (ppm) MOLYBDENUM 51 50 TITANIUM 1 0 BORON 37 53 ï»¿Additive Metals (ppm) CALCIUM 1311 1103 MAGNESIUM 835 849 PHOSPHORUS 980 946 ZINC 1212 1217 BARIUM 0 0 ï»¿No Contaminants-water, soot, fuel ï»¿Fluid Properties Viscosity 100C 13.4 13.9 TBN 2.58 4.49 Oxidation 41 42 Nitration 14 13