Well I just had my second and final service under my LongLife service agreement but had a question that I probably should have asked when I first bought my car from new So how many miles is the LongLife oil supposed to last? I did 18,000 miles in my new car without changing the oil. They changed it at the first service and then recently the oil indicator light came on (at 35000 miles) and I topped up the oil before having my second service on Monday. What's the norm for oil changes? Have I done too many miles between changes?