Well my petrol has done 120,000 miles got a tappet problem and obviously want the engine to run as long as possible, it doesn't seem to loose oil so thats not a problem, but my journeys tend to be no longer than 10 miles and sometimes does involve a lot of stop starting. The oil in there at the moment is looking thin and dirty so i was going to do an oil change but was undecided as to what oil to put in? I do a long motorway run about once a quarter and its mainly driving round town that i do but still manage to clock 300 miles a week!!