The engine has 410,000kms on it. I bought it with 200,00kms on it. I can't say what the previous owner ran for oil or oci but i go by the olm which usually is around 10,000-12,000kms. Ive used mobil 1 5w30, pp5w30 and amsoil 0w30 until i started using this truck for deliveries. Ive been running amsoil hhd 5w30 in winter and amsoil 15w40 in the summer.