A co-worker has a '02 Dodge RAM 1500 pickup with the Jeep 4.7 V8. He averages around 6k mi per year, with <4mi each way commute; no off-roading. He is currently running Amsoil 0w30 and is coming due for an OC. Should he continue with Amsoil or change to Pennzoil Platinum 5w30; and at what OCI? I have my thoughts but am insterested in the BITOG consensus.