Originally Posted by
steveG
I reckon if its knocking its been let go too long. On mine, the shells were starting to delaminate, but hadn't gone full width. It came to me with timing belt issues so I didn't get a chance to run it before I replaced the bearings, but I'd doubt if they were at the knocking stage.
IMO, if its around a '98 build with more than about 250K just pull the sump and replace them. If you really want to be tight then just check them and put it back together if OK. For the low cost of bearings I'd just replace as the main work is getting in there in the first place.
Make sure you check the top shell as that's the one that gets all the load.
If you let it go until the bearings are completely stuffed, then it can change from $50 and a couple of hours work, to a crank grind job.
Steve