The Non-AFM lifters fail in two common ways that I am aware of. 1st, the plastic trays crack and the lifter rotates and the roller starts sliding on the lobe. The other is debris gets into the needle bearings of the roller and locks it up and that scrubs the cam. My 2007 did not have AFM and I had two instances of lifters failing. The first one put shrapnel through the motor at 150K resulting in a crate motor getting put in. Can't remember what lifter was the culprit on that one. At 270K (120K on the crate motor) the #5 Intake lifter roller locked up and scrubbed the cam. I was able to catch it before it went nuclear, but I replaced the cam, lifters, trays, VVT/Cam Timing bolt, timing chain and sprockets. As
@swathdiver mentions, if a non-AFM lifter goes bad, it generally damages the cam also as they only go bad by a roller locking up or getting turned and sliding on the lobe which will start wear through the hard candy shell and get into the soft nougaty center of the cam lobe.
