I know this info has been posted before but a 'Search' doesn't find it. I even tried 'Google'. I just removed an old PowerFlo oil filter with a 'U' in the 4th position and I'm trying to determine when it was made. The filter was a 4477 and was run for approx. 9K in a Corolla 1ZZFE (with 235K) using Havoline Synthetic. It looked very good with no tears and fairly evenly spaced pleats. I feel pretty good about all the Purolator Classics that I used in the past but I wouldn't use them anymore because of the tearing issue. I wonder if Purolator cheapened their filter to meet a price point for Walmart?