Was supposed to be thanks Jim above, stupid auto spell!
J5, I went out and checked the plug over, chips are not from there. The chip on the right has some marks from machining on it. They aren't very big chunks but I have no idea how many have been pulled out of there in the past. The cab has to get pulled to get in the dif on this machine, not in the plans at the moment. I'm just wondering if this is common to find or a sign of a project in the making. The cat has 18,000 miles on her