Burning oil

Our 2001 Suburban has recently started using oil. It has 62000 miles and is in excellent condition, except for the recent increase in oil consumption. It was using a quart of oil every three to thirty-five hundred miles, now its a quart every one-thousand miles. Anyone with any experience or suggestions with this problem would be appreciated.

Sorry this is late in responding to your question, I just found this forum. I had the same problem with my 2000 Suburban. A Chevy dealer replaced the PCV valve with a different part number at about 50,000 miles, and it never burned oil again. I have almost 300,000 miles now, and it still isn't burning oil. I don't know the part number to request, but I'm sure a dealer's service area has a service bulletin they can look up.