Yes, lifter materials have not been as good as they used to be, but more than ever, the Zinc lubricating additive, known as ZDDP, has been omitted from most engine oils because modern roller engines don't require it anymore. It is very important to either purchase this additive, especially during cam break in, or use an oil that does have ZDDP in it. Shell Rotella 15W40 diesel oil used to be good for that, but I don't know if they still have zinc, that may have changed too.
