Differential Bearing Help

Ken/Alabama

Ken/Alabama

Well-known member
Got a 32 B rear axle took apart and the bearings in the carrier are Ford# A-4221 and the cups are B-4222. The pinion bearings are Timken #28156. I replaced the carrier cups with NOS Ford B-4222 and bought replacement A-4221 bearings. Bolted the housings to the banjo with two .010 gaskets but couldnt turn it. Kept adding gaskets untill it would turn with a heavy drag. The total gaskets wound up at .054 which is way too much. Took it all back apart thinking maybe a bearing or a cup wasnt fully seated but that wasnt the case. Wound up being the replacement A-42221 bearings do not ride as deep inside the cups as the original Ford bearing by .036. So that means Im .072 too wide. These replacement bearings are probably some China Junk,no numbers on the bearings and are in a plain white box. I have found no mention of the A-4221 bearing in the Ford big green book but it does list a B-4221 bearing. Whats the difference in the two? And is the Timken 28156 a replacement for these?
Thanks for any help . Ive rebuilt many V-8 rear axles but this one is a little different animal.
 
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My Green bible indicates you should be using B-4221 with the B-4222 cup. Could be your problem. I'm sure you know the difference between the round flange 32 banjo and the scalloped late 32 one which uses all 18-numbers. I would find the B- bearing instead of the A one. The housings are different from the model A so the bearings probably are too.
 
deuce_roadster said:
My Green bible indicates you should be using B-4221 with the B-4222 cup. Could be your problem. I'm sure you know the difference between the round flange 32 banjo and the scalloped late 32 one which uses all 18-numbers. I would find the B- bearing instead of the A one. The housings are different from the model A so the bearings probably are too.
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It is a round flange housing. What's got me puzzled is that it had the A prefix bearings in it with the B cups. Which bearing is correct for the pinion? The ones I removed are Timken 28156.
 
The B-4222 bearing race is exactly the same as A-4222. All the A prefix parts which were carried over and used on 32 vehicles were renumbered with a B prefix in 32. Of course, aftermarket parts might differ from OEM Ford parts.
 
John R said:
The B-4222 bearing race is exactly the same as A-4222. All the A prefix parts which were carried over and used on 32 vehicles were renumbered with a B prefix in 32. Of course, aftermarket parts might differ from OEM Ford parts.
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Ok that would explain why it had B prefix races and the A prefix bearings . So the A or B bearing should work. I see in the green parts book they aren't listing the A bearings or cups for the Model A but list the B bearings and cups for 28- early 32. Got any crossover numbers for the bearings?
 
I have had this bearing fit problem in model A's. Some bearing cups are too thick. You can have the races surface ground on the back side to get the .010 clearance on each side.

John
 
Here is the problem. This is the difference between an original Ford bearing and the China junk.You can see that the China bearing does not seat in the cup like the Ford bearing does by .043. I will be sending these bearings back and asking for a refund.
 

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From the pictures it looks like the rollers are at the same depth in the race. If you can't find the correct bearing maybe take the extra off where pointer is resting?
 
If a Model A part such as both the bearing and the race in this instance were used in the '32s, all of the prefixes were changed to B and stayed that way thereafter. The parts did not change, only the part number prefix, as stated above. Hence no more A-suffix parts of that type listed after early '32 when the change was made.
 
40cpe said:
From the pictures it looks like the rollers are at the same depth in the race. If you can't find the correct bearing maybe take the extra off where pointer is resting?
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The easiest way to lower the bearing is to surface grind the back of the race.

John
 
Ken, who did you buy the bearings from? I just rebuilt a 32 rear with round torque tube and got the bearings from Hot Rod Works. Fit was like the removed bearings.
 
Chisel said:
Ken, who did you buy the bearings from? I just rebuilt a 32 rear with round torque tube and got the bearings from Hot Rod Works. Fit was like the removed bearings.
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Got them from one of the Model A vendors. Came in a plain white box and the bearings have no numbers stamped on them. Made in China I suspect. Found some Timken bearings this morning and got them on the way. From now on when I order bearings I will ask for a brand name bearing.
 
Found some U.S. Timken bearings and installed them with two .010 gaskets and it turns silky smooth. Problem solved.
 
I just installed new Timken bearings (the NOS B4221 and B4222 bearings -- correction 18-4221 and 18-4222, thanks, David -- that I bought weren't in good enough shape) on a 1934 Rear carrier set and in the axle housings ... Assembled with no gaskets on right side, but there is a gap of 0.050 between the banjo and axle housing on left with some drag on the bearings and plenty of lash. Previous posts mentioned grinding the back of the race, but how and with what to do it precisely? Remove the cones (or seats) and bring them to a machine shop?

Any advice is appreciated to avoid too many bearing removals/installations.
 
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Late '32 and '33-'34 axles don't use B-prefix bearings and races (except at the front of the torque tube), but rather 18-4221 and 18-4222 at the inner end of the axle housings.
 
You are absolutely correct! The prefix was, in fact, 18 rather than "B". After reading so many forum posts, I had "B "on the brain when I wrote my post. Sorry!

The "B "bearings are smaller diameter then those with a "18" designation, so they don't fit the bores in the axle housings. I did install the correct bearings, but they are marginally thicker than the OEM bearings.
 
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