I have an 04 Expedition with a 4.6 swapped from an 04 Police Interceptor. I replaced the chains, guides, and tensioners when we did the swap. I used aftermarket tensioners. I did NOT replace the oil pump. The problem now is that after the vehicle warms up, I'm hearing what sounds like time chain rattle from the front cover area. Seems to be the passenger side. I took the belt off to eliminate pulley noise to verify. Is it possible my oil pump is not pressuring up the tensioners enough? Is it possible that plastic material from the original guides made it past the oil pump pickup screen and may be blocking the passage? What tensioners and oil pump do you recommend? I'm about the pull the pan and front cover to retrace my steps on the timing job. Thanks!