confused?
maybe....but no."unit" bearings didn't make an appearance in oem axles until adout '94.(at least in trucks) in dodge axles.on a w-200 it could well be a heavy duty d-44.the axle i'm referring to is a d-60-f with,believe it or not,a 5 bolt pattern.
it did not have unit bearings ,but had what amounts to a 44 sized hub.the bearings were small and closely spaced...not suitable to large tires.i think they made an appearance in about '75?they dissapeared in early 90's maybe?can't remember.
the d-61 is outwardly a d-60,but has a unique carrier.only 2-gear ratios are available,and no other d-60 carrier will swap in.lockers are not available for a d-61,iirc.
i'll try to ferret out the answers.