The wife has a 03' Civic. Purchased on 7-30-03 and it only has 2.7k miles on it. The manual says leave the initial fill in for 5k but at this rate 5k won't roll around for several more months and I'm concerned with the oil breaking down. Her commute is 3.5 miles each way. It is stop and go with about a dozen stop lights. The engine gets up to operating temp but I'm convinced that the oil doesn't get hot enough to burn off all the cooties. So do I change it at 6 months regardless of mileage on the original fill or do I just wait til 5k? This is in SoCal and this upcoming change will take her through summer where the temps are 90-100 degrees. Add the AC and stop and go and I think it could be classified as severe wear. I could be wrong, though. I've got oodles of GC sitting around but I'm also thinking of trying M1 0W-30 if someone can give me a good reason (slightly thinner?) Regardless of the oil, I already have the M1-104 (80mm oversized) filter. The M1-110 is rather dinky.