Well I switched to Mobil 1 synthetic at my local Wall Mart but i'm pissed because all they had were Fram filters and some in store brand. From what I've read on several threads here Fram sucks. I'll be bringing my own filter from Nissan or Mobil 1 next time i get a oil change. Well I definately feel a difference on how the car runs. Might be all in my head but even feels like the tranny shifts smoother. Hopefully I'll get some better mileage with this change. Thanks to you guys I'm running Synthetic. For those interested, Wall Mart does oil changes for $28 for Synthetic, preety cheap considering our cars take almost 5 quarts at almost $5 a quart but i paid $30 and got the full service(fluids replenished and chassis lube).