I've tried searching for this, but came up empty so far. So I'm hoping someone here will have an idea. For years my 06 Tahoe Z71 4WD 5.3, would properly reset the oil life back to 100%. Now for the last 2 oil changes it has decided that it doesn't want to. On the previous reset attempt it would only reset to 82%. On the most recent Oil Change it only reset to 52%. This isn't really a big problem just quite odd. I did note that when it only reset to 82% that it still took the same 10K or so miles to get down to 0%. Of course when it didn't fully reset the first time I reset it several times all going to only 82%. Now that it's only resetting to 52% I'll have to see how it does. I also use the Trip B counter to keep track of mileage between oil changes, so I do have a ready backup. I'm now using Mobile1 synthetic oil in the truck and I'm quite comfortable running 10K between changes. For me that's about 3-4 months. I had been running Havoline synthetic, but it became obvious that the shop was either putting the wrong oil in or the Havoline was breaking down at around 5K miles. I notes that around 5K the normal running oil pressure would drop by 10+PSI. Now that I'm using Mobil 1 it remains constant out to 10K.. But that's a story for a different thread.