[Joe K]

Timken Bearings today are made in China (or pacific rim) to exacting standards by the American company. There is extensive quality control - a nephew worked for a while for Timken and part of his "apprenticeship" (he is a 4 year Programming Degree) was served overseas implementing computer quality controls.

Today's production is the same whether used in a Nuclear Power Plant or for common "off the shelf" at NAPA. The only difference is that given the two, the Nuclear version has "full paper certification" and is thereby qualified for nuclear service. If you come to a bearing you're not sure of - Timken can produce that bearing's quality assurance record and tell if it was originally provided nuclear grade. If it is not, Timken can then quality it with the backing paperwork - for a price. (There is a price difference about 2x between their plain bearings and nuclear grade bearings - based on the paperwork trail.)

One imagines that NOS Timken may not have this level of quality control - made up for in part by a personal dedication. I imagine that being like that, NOS bearings might be more "hit or miss" quality wise.

I obviously don't buy nuclear paperwork for my new Timken bearings, but I do go on Ebay and look for deals. Generally anything on Ebay is about 3/4 the price of Timken bought new. And going this route, one has no way to tell NOS from more modern production.

Well, maybe the styling of the box. (This is you performing your own quality control of things you can measure - with your eyes. )

Of course someone may have put a used, possibly non Timken bearing back in the Timken box it came in - and sold the discard on Ebay.

I've seen this with Hyatt Bearings.

There is a LOT of Timken out there.

Joe K