I recently bought an 05 LLY from my father. The truck runs great, but a while back it stalled on him a few times. He replaced the fuel filter and the problem seems to have gone away. Is a dirty fuel filter a common cause of stalling, or is this just a coincidence and there is another problem? Injector Harness?

The truck has approx 110,000km (68,000mi).

Possible or it maybe he had an air leak. Common that the o-rings on the fuel filter will leak and drain the filter down or allow air into the fuel system. May also have not purged the air properly when the filter was last installed.