I have an 8100 doing something odd from tray 3 only. It will crease the paper about 2 inches from the leading margin. Usually the paper feeds completely through the printer but when it gets stuck, it wedges in the metal paper guide just past the transfer roller housing. HP says it may be a PIU problem but why does the paper make it past the input to the toner cartridge if the problem is the input. I replaced the feed separation rollers and the transfer roller and housing with temporary improvement. Anyone ever seen anything like this?