I've recently purchased a Jeep Liberty and I'm quickly approaching my first oil change at 3k miles. I'm looking for some advice on what type of oil and interval of changes meet my driving habits. I drive about 20k miles per year and am in stop and go traffic about 3/4 of the time. I really don't enjoy doing an oil change every month (which is about what I would be doing on the 3k mile schedule) but I don't want to risk only changing every 6k either. I was thinking of doing the following: 1. Complete first oil change at 3k with dino oil. 2. At second oil change (6k) switch to Mobil 1 synthetic and then follow the 6k maintainance interval. Does this sound like a good idea based on the type of driving I do? Any suggestion on what brand of oil to use for first change? All tips and suggestions are welcome.