I have a Detroit 12.7 that when I pull the camshaft out it is from a Detroit 11.1 !!! I need a new camshaft and by the serial number it’s showing up a 12.7 camshaft but the bolt from the 12.7 is more thicker than the ozone I have on it
On all three displacements for the Series 60, things like camshafts and injectors are interchangeable in the earlier DDECs. It's not uncommon to find an 11.1 built with the same cam as a 12.7 or a 12.7 with the same cam as a 14L. It's also not uncommon for someone to upgrade to a cam commonly used in a different displacement.
As far as the bolt goes, in '98 they switched from an 18mm cam bolt to a 21mm cam bolt. If you have the older engine you either have to change the gear or ream the hole to use the newer style cam.