2015 gmc 5.3L oil consumption

[Peaches]

I bought a used 2015 gmc 5.3L with 19,000miles on it. Changed the oil same week it was bought to be sure it was good to go. 3 weeks, approx 2,000 miles later I get 'add oil notification' park it immediately and check the stick. Nearly bone dry. I drain approx 3qts change filter and oil. Put 8qts in it, but it doesnt seem to be correct on the stick. No visible leaks, nor smoke out the pipe. The truck has roughly 22,000 miles on it now. What's this about??

[newdude]

Hmm...

 

I would monitor the oil level each time you fill your tank. Best thing to get an accurate reading would be to fill the truck first, and that will allow for enough time for the oil to settle back to the pan. Checking it before filling it will result in an incorrect reading. I'd give it say...2-3 fuel fills. Monitor it, but don't add any. See how far it drops. If you notice a drop, I'd set up an oil consumption test with your preferred GM dealership.

 

8 quarts on the 5.3 and 6.2 is spec.

[Peaches]

I was able to swing by a dealership. Explained the situation to the tech. I had kept the old oil and we measued it. It appeared to be 6qts that I drained, not 3. He also put it on the lift and confirmed no leaking underneath. At 8qts, hot engine, it doesn't show on the stick. When cold it shows full. His theory was that whomever did the oil change didn't add the correct amount. Since leaving the dealership, I drove approx 1,000 miles. No issues. He said consumption should be roughly 1/2qt at 5,000miles. I'll continue to keep an eye out and give an update on my findings. I travel a lot so I usually trade in every 2yrs. This is my first issue with the oil. I did notice some idling issues at a standstill. Not near as bad as the 2014 Chevy 5.3L I previously owned.