Remember folks that when you change the by-pass filter element you remove about a quart of oil with it- and need to add a quart consequently. This added quart will replenish the whatever is "used up" by normal engine operation. I changed my oil at about 12K with the GCF, but my OA said I did not need to do so. BTW- we all had a dream before the "look what's in your oil filter" thread. It horrified us all.:fork_off: