That's what I'm wondering. How the heck does a cam get twisted? Was it like that since new, or is something else really wrong? Tech said the timing marks don't line up, it's about 1/4" off I guess which is a lot. All the valves and everything look good, so hopefully it didn't damage anything else. Truck ran great for 58k miles and now the cam is twisted, so I'm wondering if that happened somehow and caused the bolts to shear off. Which brings us back to...how the heck did the cam get twisted? I've never heard of such a thing!