WreckWren
Member
Yeah I'd sooner replace bearings than go higher than 5w-40 with OEM lifters, have heard many stories about the OEM lifters hating thicker oils.It'll likely be bleeding pressure off in the cam bearings.
Only step up to a 10w-40.
Going higher will just slow the oil down from getting to the lifters and rockers.
I'd imagine the main bearings have also worn a bit, it's done a lot of Ks.