Having been absent for about 10 months I am back to work on my ‘70 Base 351C. Last November on a local jaunt (thank God for short hauls) I blew an axle seal (presumably). Intermittently drove and parked for cooling and made it home; been sitting since. Now I have it in bay and pulled axle to find a destroyed bearing. I’m believing it was a sealed bearing as it had balls and not rollers. I was under the impression that these cars were equipped with open taper bearings with an outer seal to prevent gear oil bypass. All I’m finding are sealed bearings - mine did NOT have an outer seal cup. Are sealed bearings the present “norm” - or am I missing something. Thanks in advance.
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Tappered is the norm.
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Thanks for that - I am confused though as to why I can’t find outer seal cups for them.
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It is call a dust cap.
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You said axle. Are you talking about the rear or the front? The front has tapered roller bearings with an inner seal and the outer grease cap. The rear axle has ball bearings with rubber seals the shafts pass through.
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Rear axle. I think part of my problem is uncertainty as to proper nomenclature. I’m given to understand that there is a housing seal (one is in place on mine) a lock ring/adapter that holds the bearing in place on the axle, the bearing and then an external seal that cups the bearing. The existence of an inner housing seal on mine, and the fact that the bearing was a ball bearing model, indicates that it was likely a “sealed” bearing and didn’t require oil bathing or an external seal (which is non-existent on mine). If it should in fact be a tapered roller bearing, it would lead me (possibly ignorantly) to believe that it would rely on gear oil slosh for lubricating so would not want an inner housing seal but would require an outer seal. All I’m finding are sealed bearings for the 28 spline axle, and only find taper bearings for the 31 spline axle.
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It’s a sealed bearing with a retaining ring that holds it on the axle with a press fit. There is an inner seal that keeps the differential gear oil inside the center part of the axle housing and away from the sealed bearing. There is no outer seal. There should be a metal or paper gasket between the backing plate and the flanges on the outer ends of the axle housing
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scroll to bottom
TIMKEN RW207CCRA
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Perfectly descriptive - yes, there is a tin gasket behind the backing plate. Thank you! Is it possible that the “other” set up is only for the 3.1” 31 spline set-up?
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Thanks Bill - that is similar to what I’ve been finding, and the RW207CCRA is the number I’ve been looking at. Same question to you: are the tapered open bearings only for the 31 spline axle?
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Never seen any bearing that was for sale that was not sealed for the rear axle. The odd thing is they also sell seals. In any case all of them have always been that way.
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And you ought to know; thank you Royce.
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First, apologies for apparent “misplacement” - moderator please move discussion to “Restoration & Repair”. For any future seekers who wind up on this topic there ARE apparently two different set-ups; still unclear as to when one is used vs the other, but since mine had ball bearings and no outer seal I will be reinstalling same. Here are pics of the ball bearing and taper bearing set-ups. If I discover anything else I will post again. An added note for now is that the seal outside edge wants to be coated with an oil impervious sealer - I was steered to “Hylomar Blue”.
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The tapered one looks like an outer wheel bearing for the front wheel. Never seen any like that for the rear.
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I have, fairly common in mid 70s and up F-150s and Broncos.
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I’m satisfied to at least know (?) that I’m good to go with the sealed bearings and no outer seal; apparently the taper rollers with outer seal cup are for high performance/offroad/extreme duty. When I finally get all straightened out mine will only be a grocery getter. Next problem comes with U-joints.
All of the 8” & 9” rears used in Cougars 67-73 had the sealed ball bearing wheel bearings with the inner seal only. Some later trucks used that tapered bearing as mentioned. Keep in mind Rock auto is great at listing parts that are not for the application.
67xr7cat - Thanks for that (confirming) info; and the Rock Auto tendency pervades many other providers as well - hence my issues.
I’ve had good luck with JB Weld. 
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