1969 C10 Front Wheel Seal Not Flush

[NolanAM22]

I have a 6 lug '69 C10 with 4 wheel drums that I am currently repacking the front wheel bearings on.

I did not remove the races and I am reusing the bearings. The races looked to be seated properly in the hub. I had no previous problems with the bearings, just doing this for maintenance.

I am at the point where I am putting the new front wheel seal back in after putting the inner bearing back in and the seal (National Bearing Part# 9015S) is not sitting flush with the hub surface. The top surface of the seal is about 0.160" (~5/32") above the wheel hub surface, as measured by calipers.

I drove the seal in with a seal driver and noticed that the pitch of the noise changed as I was hitting the seal, indicating that the seal was seated properly onto the top of the bearing race surface.

I have seen on these forums that the seal does not sit flush with the hub surface, but my question is: How much higher does the seal sit? 5/32" seems like a lot higher than it should be.

The previous seal that I used was National Bearing Part# 8871 and it sits flush with the hub surface. Problem is, I think I was given this by mistake last time I did the bearings. I just assumed it was a different or more modern style seal. Turns out according to Rock Auto parts catalog, it was meant for a 71-86 C10, NOT a 69 C10.

My hub casting number looks to be 3883 31030, but it is hard to tell. The number I am referring to is on the inside diameter of the hub casting.

Important measurements:
Spindle shaft - inner bearing mating surface to hub backing plate: 0.465"
9015S Seal thickness: 0.505"
8871 Seal thickness: 0.260"
9015S top surface to wheel hub surface: 0.160"

*Note* in the picture the calipers read 0.460" on the spindle depth measurement. I probably didn't have the calipers straight/parallel to the spindle longitudinal axis.

[kwmech]

Ok, so get the correct seal. With the amount of 'press-in' that seal has, odds are it will pop off after awhile

[truckster]

Did the previous seal leak? If not, it seems like the easy answer.

[NolanAM22]

Thanks for the quick reply.

The new seal (9015S) is the one in question. It is the seal that the catalog calls for and supposedly the proper seal for my application. I have it installed in the pictures, but it seems like it is sticking out too far past the hub to me.

The old seal (8871) was flush and didn't seem to cause issues, but according to the catalog is not the proper seal for my application. The grease toward the inner bearings was pitch black when I removed the hub to repack, so maybe the old seal wasn't mating properly and keeping brake dust out?

The problem is, I have the proper seal installed in the pictures, but it doesn't seem to be fitting right imo. Maybe it is fitting right, but I don't have the old seal to look at because I was given the wrong one the last time I did the bearings. This is why I was coming here, to ask if this looked right or not. I also wanted to know what the proper height of the seal should be above the hub surface in a proper install.

[Smitty]

What makes you so sure that the 9015S is the correct one? I googled the '69 application for wheel seals. And went to the Auto Zone site and they also list the 8871 as applicable for some C-10's. In my experience they have always fit flush. Maybe check somewhere other than Rock Auto to verify what you need. What you are showing isn't normal.

[NolanAM22]

According to the Rock Auto site, the Oreilly's site and the NAPA site, they all call for the 9015S for the 1969 C10 with light duty brakes (2" spindle, 2.561" hub bore).

If you go look at https://www.finditparts.com/products...nal-seals-8871 it says 1971-74. I confirmed that with Rock Auto.

Yeah, I am not sure why it wouldn't fit flush either, seems like you would want the hub housing to reinforce the seal if it saw any type of load. Of course, the seal has already been pressed in 0.345" of its total 0.505" width, so maybe that is enough.

Just weird to me that it sticks out that far, just doesn't seem right.

[NolanAM22]

Posting this for anyone seeing this in the future. If anyone knows that this seal is not supposed to stick out this much, feel free to let me know, but I ended up sticking with the seal pictured (9015S) instead of the 8871.

Test fit the hub with some grease on the seal to see if there would be grease on the backing plate when I removed it. There was no grease, so it seems like it has clearance.

I also measured from the inner bearing surface to the top of the seal surface, which ended up being 0.330". That measurement was less than the 0.465" measurement from the spindle shaft - inner bearing mating surface to the backing plate (pictured above).

Seems like both methods showed I had clearance. I will report back if I'm wrong and my truck has some type of catastrophic failure

Still not sure why the seal sticks out that far, when typically the seals I've seen are flush.

[NolanAM22]

Side note: Does anyone know how to edit the title of a thread?

I meant to put "1969 C10 Front Wheel Seal Not Flush"

Forgot to put in "Seal"

[dmjlambert]

There are a few items catalogs have wrong for our trucks, even across multiple vendors as you have documented in this thread. For me, comparing the new part going in with the part coming off the truck wins over what is right according to the catalog. There is a possibility the seal "given this by mistake last time I did the bearings" was given to you by a savvy parts rep or a parts rep using and old paper catalog.

[NolanAM22]

Originally Posted by dmjlambert

There are a few items catalogs have wrong for our trucks, even across multiple vendors as you have documented in this thread. For me, comparing the new part going in with the part coming off the truck wins over what is right according to the catalog. There is a possibility the seal "given this by mistake last time I did the bearings" was given to you by a savvy parts rep or a parts rep using and old paper catalog.

Could be.

I looked through this site for similar issues and came up with these threads:
https://67-72chevytrucks.com/vboard/...d.php?t=348435
https://67-72chevytrucks.com/vboard/...d.php?t=785166
https://67-72chevytrucks.com/vboard/...d.php?t=560246

Each of these threads has someone saying that their seals do not seat flush, but I didn't see anyone mention the height at which they were above the hub surface (distance between top of seal and top of hub) on a C10. One thread is about C20's so not directly relatable to my situation.

I couldn't find info on wheel hub casting numbers, but if my hub is OE, and the bearings/races are correct, then the seal should also be correct unless the catalog isn't right like you mentioned OR I'm installing incorrectly.

In the threads mentioned above, the C10 guys mention the same 9015S seal, but they could also be running into the same problem of the catalog being wrong. But if the catalog is wrong, I would assume that info would be all over the place on this site, right?? Everyone with a C10 in that year range with front drums would have run into that issue.

The reason I am questioning the old seal is because it is recessed inside of the hub and after some crude measurements, it seems like it might be sitting on the very edge of the flat portion of the spindle. The grease that I cleaned out seemed to be pitch black (originally tan colored). I wondered if that indicated that brake dust was getting into the bearing cavity.

I just wanted to come on here and run it by the people who actually know these trucks and see if anyone had some knowledge about it.

[jaros44sr]

Is it possible that some of the old seal broke off and it is sitting in the groove where the seal goes, look in the area where the seal goes and make sure it has no debris in it
Just a thought

[Steeveedee]

Originally Posted by dmjlambert

There are a few items catalogs have wrong for our trucks, even across multiple vendors as you have documented in this thread. For me, comparing the new part going in with the part coming off the truck wins over what is right according to the catalog. There is a possibility the seal "given this by mistake last time I did the bearings" was given to you by a savvy parts rep or a parts rep using and old paper catalog.

Not his case, but there is also the problem of parts being "boxed wrong", as we call it in the parts biz. I rebuilt the rear brakes on my truck back when I converted the fronts to disc. It took several tries to get the correct right rear brake adjuster from the local parts store. I got a 1t part in the box, and it was sent back. The same part came back as the replacement. The owners of that store have known me for a long time and know that I know what I'm talking about. We finally ordered TWO, so that the "boxed wrong" part and a correct part got delivered. The wrong one got sent back, and I got my brake job done.

[NolanAM22]

Originally Posted by jaros44sr

Is it possible that some of the old seal broke off and it is sitting in the groove where the seal goes, look in the area where the seal goes and make sure it has no debris in it
Just a thought

No I cleaned it out really well. That would be a tough thing to miss imo, but I'm sure its happened.

With the inner bearing and seal removed, if I measure with calipers on the inside of the hub, from the bearing race top surface to the hub top surface (the place where the seal would be sitting), I get 0.345" or so. The height of the seal is .505", so it should be sticking out 0.160" or so when seated on top of the race surface.

When I measure from the hub surface to the top of the seal surface, I get about 0.160", so that math checks out that it is seated all the way to the top of the race.

I feel a little more comfortable knowing that the other threads tagged above had the seal sticking out past flush as well. I think it has enough side wall surface engagement to make sure the seal is square and to keep it in its place for its life time. There is also no contact with the backing plate.

I just figured that someone would chime in that had done bearings and mention that this is normal, but that is not what has happened. Id be curious to see what seal someone else used and how it fit, if they had the same application as me (69 C10 4 wheel drums, light brakes).

I guess time will tell if I am right or not.

[PanhandleShantyman]

I recently replaced my front wheel bearings on the 1969 GMC 1500 and initially bought 9015S seals. As you saw, they don't sit flush to the hub. I basically crushed them trying to whack them down flush, figured I had the wrong part, and then ordered supposedly NOS seals from NAPA part # 19757. These parts had identical stampings to the old seals I pulled out of the hubs. However, these also didn't sit flush to the hub and they were noticeably taller than the seals I pulled out of the hub (see picture)! Oh well, I put them in anyway and mounted the hubs and they seemed to have enough clearance not to matter, so I've been driving mine and so far so good. By that time I'd spent $60 on grease seals and waited a week for parts to get back on the road with, so I figured I'd cross my fingers and go with it.

[NolanAM22]

Originally Posted by PanhandleShantyman

I recently replaced my front wheel bearings on the 1969 GMC 1500 and initially bought 9015S seals. As you saw, they don't sit flush to the hub. I basically crushed them trying to whack them down flush, figured I had the wrong part, and then ordered supposedly NOS seals from NAPA part # 19757. These parts had identical stampings to the old seals I pulled out of the hubs. However, these also didn't sit flush to the hub and they were noticeably taller than the seals I pulled out of the hub (see picture)! Oh well, I put them in anyway and mounted the hubs and they seemed to have enough clearance not to matter, so I've been driving mine and so far so good. By that time I'd spent $60 on grease seals and waited a week for parts to get back on the road with, so I figured I'd cross my fingers and go with it.

Thanks for the feedback, this is very useful!

And were the seals that you pulled flush to the hub surface??

What was the thickness of the old seal by chance? My new seals were 0.505"

[pjmoreland]

I did a parametric search on the Timken website using the same shaft and outer diameter as the seal you used, and it came up with another seal that is .250" wide. It might be worth giving it a try.

Timken 4739

https://www.summitracing.com/parts/TMK-4739

https://engineering.timken.com/engin...l/seal-search/

[RichardJ]

>>The grease that I cleaned out seemed to be pitch black (originally tan colored).<<

You expected 50 year old grease to look as new?
Unless you have knowledge of when the last time the bearings were repacked, age and a number of heat cycles will affect at least the appearance of the grease. It doesn't mean the seals were leaking.
If the seals had to be driven in to the height they now are and no others are available, it seems you have answered your own question.

[NolanAM22]

Originally Posted by pjmoreland

I did a parametric search on the Timken website using the same shaft and outer diameter as the seal you used, and it came up with another seal that is .250" wide. It might be worth giving it a try.

Timken 4739

https://www.summitracing.com/parts/TMK-4739

https://engineering.timken.com/engin...l/seal-search/

Thanks. The Timken 4739 looks very similar to the 8871 that I pulled off, with the exception that the 8871 has a flange to mate against the hub top surface.

I'm not a seal expert, but does a seal need to be bedded against some type of surface or can it "free float" for lack of a better word? The 8871 is bedded against the top surface of the hub via its flange and is 0.260" thick. The 9015S is bedded against the top of the race surface via its bottom surface and is 0.505" thick. The race top surface to hub top surface is ~0.340", so the Timken 4739 would be "free floating" and not bedded against any type of surface. Only the friction of the side walls would be holding it in place. I wonder if that would make it more prone to being out of square with the shaft, not sure.

I appreciate you looking into it, PJ.

[NolanAM22]

Originally Posted by RichardJ

>>The grease that I cleaned out seemed to be pitch black (originally tan colored).<<

You expected 50 year old grease to look as new?
Unless you have knowledge of when the last time the bearings were repacked, age and a number of heat cycles will affect at least the appearance of the grease. It doesn't mean the seals were leaking.
If the seals had to be driven in to the height they now are and no others are available, it seems you have answered your own question.

I put in new bearings and seals about 10 years ago. That's why I was mentioning the 8871 seal, because it looked like I got it by mistake based on what the catalog calls for.

The grease at the inner bearing near the seal was pitch black, the grease toward the outer bearing near the castle nut was still more of a tan color. That was my reasoning.

But yeah I'm sticking with the 9015S seals for now.

[pjmoreland]

Originally Posted by NolanAM22

Thanks. The Timken 4739 looks very similar to the 8871 that I pulled off, with the exception that the 8871 has a flange to mate against the hub top surface.

I'm not a seal expert, but does a seal need to be bedded against some type of surface or can it "free float" for lack of a better word? The 8871 is bedded against the top surface of the hub via its flange and is 0.260" thick. The 9015S is bedded against the top of the race surface via its bottom surface and is 0.505" thick. The race top surface to hub top surface is ~0.340", so the Timken 4739 would be "free floating" and not bedded against any type of surface. Only the friction of the side walls would be holding it in place. I wonder if that would make it more prone to being out of square with the shaft, not sure.

I appreciate you looking into it, PJ.

I don't think free floating would be a good idea since it might not be straight. Could it be driven in until it hits the bearing race?

[NolanAM22]

Originally Posted by pjmoreland

I don't think free floating would be a good idea since it might not be straight. Could it be driven in until it hits the bearing race?

Well it would be under flush of the hub top surface for sure. So the next contact point would be the actual inner bearing, not the race, since the inner bearing sits a little bit above the top surface of the race. No bueno.

[pjmoreland]

Originally Posted by NolanAM22

Well it would be under flush of the hub top surface for sure. So the next contact point would be the actual inner bearing, not the race, since the inner bearing sits a little bit above the top surface of the race. No bueno.

No bueno, indeed.

[PanhandleShantyman]

Originally Posted by NolanAM22

Thanks for the feedback, this is very useful!

And were the seals that you pulled flush to the hub surface??

What was the thickness of the old seal by chance? My new seals were 0.505"

The seals that I pulled, to the best of my recollection, were flush to the hub. I chucked the old ones already before I realized what a hot topic this would become.

That was the bizarre thing. The old seals and the new ones have the same codes stamped on them. They just aren't the same height! Oh well, as best I can tell, they both work.