Rear axle bearing puzzle
 

Another quagmire... I pulled apart a '36 differential only to have the roller bearings and cage fall off one of the differential sides. Nothing seems broken or bent. Why it fell off is a mystery. It appears that the bearing was replaced sometime in the past probably a old stock aftermarket part. The other side- no problem. Looks like I will need a new bearing and race but, what? Evidently, Ford in '36 made two different axle bearings, There must be a difference. Does anyone have a clue how to tell an "early" from a "late?':confused:

If it is any help, I've enclosed two pictures of what I am looking at.

Tom

Re: Rear axle bearing puzzle
 

I would think there should be a number on the bearing.

Bob

Re: Rear axle bearing puzzle
 

I only see 1 bearing for a 36. 18-4221 (32-36 passenger). The other bearing B-4221 is for the 32 B rear end that has only 3 spiders. At least that is how I read the green bible info.

Re: Rear axle bearing puzzle
 

I've seen similar on (non banjo rears) where there wasn't enough-or any-preload on the bearings...i/e loose hubs on floating rearends and the like.

Re: Rear axle bearing puzzle
 

I don't see anything particularly unusual in the picts. Just that one side has a failed bearing, ie the cage came apart. No biggie, just replace the bearing (s). If it were me, I would say hopefully with old, original parts, even select used if you can find a matched bearing with its original race. If you must buy new, be careful with the shimming process - I've read here that new bearings might have dimensional variations??
As far as I am aware, I don't believe there is more than one carrier bearing, for 35 to 48.

Re: Rear axle bearing puzzle
 

I am pretty sure it is 18-4221 for 32-36 and 68-4221 for 37-48 passenger cars and commercial vehicles 37-47 Green bible page 127. Those bearings are readily available in Timken brand.

Re: Rear axle bearing puzzle
 

Duece Roadster has it correct, actually, there is the identical bearing on the other side to help clarify. If it were me, I'd rebuild the whole assembly, after all, if one bearing has failed, what about the rest?- they've all done the same mileage!