Had this problem really bad 6-8 months ago but fixed it(to within GM specs, less than one quart per 1000 miles)with new to me heads. Stupidly I switched from 10w40 to straight 40 OReilly. It is well on its way to failing the GM test.
Also, I have an oil catch can that will get a little oil in it between changes but when i checked it after getting the low oil light it was full, to the point of the part that hangs down into the can being in the wasted oil.
Tomorrow should be about 1000 miles and I will be going back to multi vis.

Any thoughts? I might consider a ring job after I fix another car that will haul everyone around.

 

Try the "Valvoline Maxlife Oil" for high mileage engines.

I have tried other brands and this is the one that worked for me. I run 10W-30

I currently have 164,xxx milage and I was burning upwards of 2 Quarts every 2000-2500 miles at around 80K.

 

I don't see your location but I'm wondering why 10w30?
I'm in nwhouston and it was 92 two days ago, when my c5 came home and puked a bunch of coolant
I may wait for your response before I buy any. BTW I'm at 207,6XX.

 

Im in CA

Factory calls for 5W-30

10W-30 made the lifters quieter on my truck. AT the time they did not have a 5W-30 high mileage oil on the market.

For me, It seemed like engine had to worker harder with the thicker 10W-40.

I would stay with same weight that your already using.

 

FWIW, when I worked at GM, I had a powertrain engineer tell me that 40wt oil in these engines will make the rings stick in the ring lands. And that would lead to increased oil consumption.

 

Ahh!
A definitive answer. And it seems I may be responsible for my own condition.
Fudge with nuts. Going to the store tomorrow during lunch.
Many thanks guys.

 

Could need a new PVC valve. Mine was burning oil like crazy maybe a qt every 500 miles, I replaced my old PVC with the new strait through version and it started burning maybe 1/2 qt every 3000 miles.

I drilled out my oil cap and put a filter on it to relieve some crank pressure and switched to castrol 10w 40 high millage and not a drop of oil has been burned since.

 

69', I have an opinion catch can; shouldn't that eliminate hat possibility?

 

I don't know the answer to that as I have never had one or learned about them. But the PCV valve was around $8 so it would be a cheap attempt to fix it.