Back in October I gave Mobil 1 10W-30 a try on a 6 month interval (less than 3K). I've been checking it regularly because I've heard all of the high mileage consumption stories. 90% of those miles were racked up on "around town" short trips with a couple 100 mile trips in between. Today I checked and it was about 1/4 of a quart low. When I went 3-4 months / 1,500 miles on Pennzoil 5W-30 the dipstick never showed a change. I checked under the hood and under the car, it's definatly not leaking and it doesn't blow smoke at all. The engine is a 2.4L DOHC (GM) with 83,700 miles. Is this just normal for a 83,000 mile engine? I'm thinking about going back to Pennzoil 5W-30 and shorter drains or Mobil 1 Drive Clean Plus.