Other mistake: Preacher has a large bold tattoo at the center of his chest below his neck that changes repeatedly. For example, it's dark and clear when they capture the deputy, but it's smudged and partially gone when Preacher forces Stella, the deputy, and Ralph into the 18-wheeler. (00:29:10 - 00:36:50)
Continuity mistake: Preacher forces Ralph to stop the sheriff, so when Ralph flies over and pulls the driver's door off the squad car, we see the Sheriff behind the steering wheel wearing his uniform shirt and dark colored pants of some sort, but when the Sheriff stands up his uniform shirt is properly tucked into his normal tan pants, same as earlier. (00:39:05)