Number one main bearing

[sext7366]

Ok got my block and parts, and i am starting to assemble, I got the clevite 77 bearings.  In my service manual is says that the number one upper bearing is not interchangeable, and should be chamfered for the timing chain, but I cannot tell a difference in the bearings.  Are the all smaller bearings the same, or am I missing something?

[TylerCharger69]

there is no chamfer on the number one bearing?....If not....it may mean  that it applies to another application other than Mopar....as far as I know....they are all the same except for number 3 of course.....they are all stamped upper and lower  and also  stamped is the size...whether it's a std. fit  or 10 under...or 20 under....etc. etc. etc......Just examine the edges very carefully  to make sure there is  or isnt a chamfer on them....just in case

[sext7366]

well they all appear to be chamfered, so I didn't know if there was a difference or not.  Since the book pointed it out, I thought the difference would be noticeable...oh well.

[John_Kunkel]

Only the factory bearings will have the chamfer, the aftermarket never worried about it.

If you look at the part number on the back of each individual bearing shell you'll notice they're all the same (except for the thrust bearing shells).