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Ive noticed between oil changes im losing oil but i dont see any oil on the ground. Im curious what amount of oil is normal if any to burn overtime. I would over the course of about 7000 miles (I know im overdue) i lost about 2 quarts of oil does that sound normal??
 

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As a general rule. Some engines can burn up to a pint every thousand miles and deemed normal. I in my experience with new and used GM engines over my 3.5 decades of driving, I never had one burn oil. And if memory serves, that is over 30 vehicles.

Pat
 

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What vehicle? You're talking about a loss of about a quart every 3,500 miles.

I consider that excessive for a newer vehicle, although it's probably within tolerance for just about any manufacturer.
 

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Ive noticed between oil changes im losing oil but i dont see any oil on the ground. Im curious what amount of oil is normal if any to burn overtime. I would over the course of about 7000 miles (I know im overdue) i lost about 2 quarts of oil does that sound normal??
Jared, you don't give enough info, but you are not alone in this. The year, engine size, and especially IF it is an AFM engine are important. AFM stands for Automatic Fuel management. AFM deactivates 3 of the cylinders under a light load, assuming we are talking about a V6. (I don't know if GM uses AFM on the V8s in Impalas) AFM causes oil to be burned, but NOT like engines normally burn oil. With a normal operating cylinder (burning fuel!) the cylinder pressure from combustion pressure gets behind the rings, mainly the oil control rings, and helps the rings scrape the oil downward back towards the crankcase. Without pressure behind the rings, the rings can push oil upwards. This is a problem with AFM which on the surface seems like a great idea. This is why you don't see a leak, IF you do have an AFM engine, like my 3.9L V6, this is why you are seeing oil consumption, and the type of driving you are doing has a lot to do with it. On my 2008 LTZ there is a readout on the dash on whether it is running on 6 cylinders or only 3, so is this something you see on your dash? Since you don't see any leaking I suspect you do have an AFM engine. Now if you also have a 3.9L V6, know that the crankcase only has a 4 quart capacity and something I don't care for myself, so I WATCH it, and I only use a full synthetic oil. Now, Back to the Piston Rings, when a cylinder is deactivated and there is no pressure behind the rings, oil gets passed the rings and into the combustion chambers to be burned. Under a light load like highway cruising is where you will see oil consumption. GM has used AFM with some of their V8s and they no doubt have the same problem. I heard that they don't supply parts to repair AFM any longer but I don't know this for sure. GM does have kits to convert these engines to non-AFM which requires a new cam and I THINK the engine would need be pulled to do that on front wheel drive cars. My 3.9L will burn oil as I said but I keep watch on it and I don't drive it enough for it to be a BIG problem for me. Hope I made this clear enough for you and others also. (Oil gets on the cylinder walls in the first place by normal engine rotation and by oil squinters to cool the bottoms of the pistons if the engine is so equipped.) If you only burn 2 quarts of oil in 7000 miles that is not really that bad, again the type of driving you do is a factor, and if your engine like my 2008 only hold 4 quarts, I sure wouldn't want to driving with the crankcase 2 quarts low, and maybe you don't have an AFM engine?
 
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