Hi, I will start with the fact that I am super old school when it comes to oci I usually do 3k. After reading some threads I have been considering going to 4k oci. What do you guys think, I have a 08 Honda CRV and a 06 Toyota Yaris and usually go with conventional YB or valvoline 5w20 which ever is on sale and use conv puralator or if pure one is on sale I pick up that one, this is mainly on the crv. On the Yaris conv yb or valvoline 5w30 and also Puralator conv, pure one or oem. What do you guys think, I keep cars for a looooong time, will this new oci affect my longterm engine life?