Insert bearings are lined with babbit. Its just they are not poured/scraped... but applied with much more precision. So we all still have 'babbit pounders' if you think about it
Chevvy/GMC/Ford trucks had insert bearings in the early 40's. My 42 Ford and 43 GMC had them as original equipment. Not sure why Chevvy took so long to get them out of the civvy engines.
And one man's 'knock' is another man's 'tap'. Rattles seem to be universal.
