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Disappearing oil

This vehicle has been losing about 2 Qts of oil between oil changes. It has a little over 100,000 miles on. I have had this vehicle since it was new.
I change the oil about every 4,000 miles. I see no smoke coming from the exhust and I have changed the PVC valve. This vehicle is a 2003 Buick Rendezvous
with a 3.4 liter engine. Thanks

It looks like you are burning a quart of oil every 2,000 miles. For an engine with 100,000 miles I would say you are doing fine. Your oil is most likely burning up due to slightly worn valve guides and/or slight wear in the pistons around the rings. Both are normal for this mileage and your oil consumption is nothing to be concerned about. Many drivers of new cars are seeing oil consumption in excess of what you have.

Just to add, the catalytic converters are very good at preventing smoke from the burning oil from coming out the tailpipe at this rate of burning. That’s why you see no smoke.

Agree that this level of consumption is not unusual in a car with that many miles.

Make sure you regularly check the oil and top up as required. I had a Chevrolet that consumed as much and we drove it to over 300,000 miles without any problems.

Many car engines burn that amount of oil from day one…It’s considered normal oil consumption. Just be sure to check it at least once a month and top it up. Don’t let it run 2 quarts low…