2020 Tahoe, 5.3l, Dynamic fuel management. 85k miles engine has never been touched.
I bought some synthetic 0w20 oil and changed it. It had about 4500 miles on the oil amd the OLM was showing 43 percent left. The oil lo was a darker brown. I did not take a sample to have it analyzed.
With all the lifter and camshaft problems these are know for I question if I should follow the OLM.
When I had my prius I changed the oil at 10k intervals. I didn’t have the car long enough to know how far the engine would go but they are known for longevity while the 5.3 with cylinder deactivation is known for trouble.
Get some fresh oil in that thing is what my heart told me and after seeing the oil and smelling it im glad I did change it.
Previous owner changed the oil at 20 percent on OLM generally.
Well I change oil when it is about 50%. Thats about 5000 miles on the Acura and 3000 on the Pontiac. I’ve had the discussion on how much work they put into coming up with rhe figures, but on the other hand I’ve put 300,000, 400, 500k without an engine problem. My money not theirs. Oil is cheap. I do use the recommended weight oil though. Not convinced 10w or 5w is better than 0.
I drive a Chevy Volt plug-in hybrid. You can go weeks or a month or two without the engine running. I only go by the OLM with oil changes because miles mean nothing for that. My Volt has 95,000 miles on it but the engine may only have 9 or 10.
I stopped following the Chevy OLM on my non-AFM 5.3 about 8 years ago. I stopped because I don’t drive the truck that much and the OLM doesn’t have a calendar! I’d get to one year with 3000 miles and the light would not come on. So my change intervals are one year.
Previous to that use, I’d follow the OLM. It varied between about 4500 miles (towing the race car several times) and about 7500 miles (my highway commute to work). The oil stayed visually decently clean between changes. And I always used synthetic oil.
I used the OLM on my 1998 Regal (3.8L) and our 2003 Silhouette (3.4L). Oil changes were about 7000 to 7500 miles and the engines ran well, with both exceeding 175,000 without burning oil. If I just bought this SUV, I’d change the oil and trans fluid immediately. You might also use one or two successive tanks of gas with an engine treatment to remove carbon buildup on the back of the intake valves. The coolant is probably OK at 85,000 miles. If you are concerned, test it.
With all due respect OP…you have another post going about what kind of oil to use for your GM vehicle. This is apparently a very real concern for you.
There’s no “right” answer here. My advice, as seems to be the case with others is…do whatever helps you to sleep at night. Personally I change the oil in my cars every 6 months or 6000 miles, whichever comes first, regardless of the OLM, and with full synthetic oil. It works fine for me. I’ve never had an engine problem related to oil.
Just decide what works best for you, make a decision, and worry about other things.
If you are concerned about longevity on these, get an AFM/DFM defeat module and then follow the OLM. If you leave it as is, I would change the oil at 5000 mile intervals.