Except for a transmission oil leak about 2 years ago, my minivan has been reliable and low-maintenance. I usually get the engine oil change every 3500 miles or so. However, the last oil change suggested that the engine seems to be burning oil. I've been checking oil levels on and off since, and yesterday I discovered that the oil level was off by about 2 quarts. There is no evidence of oil leaking on my garage floor. I don't want to be constantly checking the oil, so I think I need to consider having a new or rebuilt engine installed. How do you recommend that I go about researching the cost of a rebuilt vs. new engine installation and making a decision? Thanks.