Just received my oil report back from Blackstone for one of my 03's. The report showed a 11 in copper (5 is the universal avg. ) and a 5 in silver (a 1 is the universal Avg. ). All other numbers where okay. Blackstone recommends another sample at 10,000 miles. Oil is Amsoil Sig. 5w/30 with Amsoil extended oil filter. I did change the oil and filter. The oil had 10,950 miles, truck now has 140,010 miles on it. Does not burn any oil between changes. I do oil changes every 10,000 miles or within a year, which ever comes first. The oil that was sampled was eleven months old. I will try to post a copy of the report, by the way, TBN was very good (7. 3). Thanks for any help. Frank