It could. I know that Marty said they couldn't find a seal,based on their measurements,but he was researching 1966,not 71-72. I know he said his mechanic used some sort of makeshift seal. Yes,the seal helps keep the bearing seated into the race.The bearings also need to be installed into the axle so the race is facing out. It goes into the axle tube first. There is a shoulder inside the axle tube that the race seats against. A seal that is too thin allows the bearing to move out of the race,causing unwanted play,leaking,and possible noise.
I pulled the axles out today. The bearing and seal that was used was a A-9 and a 2146. DS bearing was actually separated from race while PS was not. I ordered the Timken SET-9 bearings and 712146 seals. So your saying the outer race goes into the axle housing then? Why would one bearing have the race separated while the other bearing almost be like a sealed bearing?
send pictures of what you have. Some bearings were NOT tapered so the bearing will look different...All depends if you have orgianl GM or aftermaket bearings. Send the pics and will ID them for you.