9" axle seal replacement

[BillsFan76]

So this is the 3rd post I have on tech support and haven't finished the other 2 yet. Sad day. Alright, I bled the air out of my brakes last weekend as they were awful and it fixed it. Unfortunately when I removed the rear passenger tire I could see the axle seal was leaking badly. I got the parts and got the seal out this morning and after popping the seal out there's two metal pieces inside the axle housing. I assume these are pieces of the ring and pinion? Should I bother replacing the seal and putting it back together at this point or just take it somewhere and have them look at it? I have no idea how to do anything with the ring and pinion and I know it's easy to mess up and do big-time damage. Here's a picture of the two pieces I pulled out with a magnet, is it safe to put it back together and drive it somewhere ?

[BillsFan76]

Is has a posi rear end, are those pieces of the posi trac and can it be removed and ran as an open differential? Anywhere local in Denver any of you can recommend to bring this and have that done? Thanks everyone

[Justin]

How big are they, and is it a large or small bearing housing? From your description, it sounds like they were found down in the end of the axle tube and I'm guessing it's small bearing since you had to extract the seal. They could be R&P bits, but it's tough to know for sure without disassembly. Could also be chunks of roller bearing if it's a large bearing housing, or bits of carrier bearing. I wouldn't drive it, but that's an individual call. Extracting the center section isn't that hard if you've got basic mechanical ability and a decent socket set. I'd start by double checking the wheel bearing, then pulling the other axle. From there, you just disconnect the driveshaft and remove the 9 or whatever nuts to take out the center section. My guess is that a quick inspection will tell you what's wrong. If it needs to be professionally serviced you can just take the center section to the shop and save yourself several hundred dollars having it removed.

[BillsFan76]

When you say start by checking the wheelbearings, do you mean the bearing pressed on the end of the axle I removed? Also, attached is a picture of the metal pieces in relation to one of the 4 nuts that holds on the axle shafts.

[Justin]

Yes, that's what I meant, but it sounds like you've got wheel bearings that would be little balls instead of tube shapes. Those look like R&P teeth, but could be something else as well.

[BillsFan76]

Here are pictures of the bearings on both axles, they seem fine to my untrained eye :)off to Walmart to get a drain pan to pull the pumpkin out and see what's in there. There was another similar sized piece in the other axle housing.

[Justin]

Those look fine, or at least haven't out any chunks. Check them for play, and as long as they're out you might as well install new ones if they haven't been done already. Sounds like your plan to dig deeper is a good one.

[BillsFan76]

Would you replace the axle bearing on the axles were out?I have no way to press those bearings back in and haven't done it before, is that something I can bring somewhere and have them do for me if you think that should be replaced?

[BillsFan76]

I meant to say would you replace the axle bearings just because the axles have been pulled out? If they have no play would you still put new ones in?

[BillsFan76]

One of the bearings is completely tight when spun, the other axles bearing has a tiny play in it. Not sure if it's enough to matter but compared to the other it has a little movement.

[Kinder]

The seal usually goes because of axle movement, when one side is worn I play it safe and replace the whole lot.

[Justin]

What kinder said. How did the gears look?

[Viperwolf1]

Those look like spider gear teeth. Common problem on 2 pinion diffs, maybe more so with the track lock. I say pull it all for inspection. It's possible they were leftover from previous breakage and repair but you don't know until you look at it. I would also replace both axle bearings if one is questionable.

Both stock large and small bearing axles use similar inboard seals. 11 inch brakes are always large bearing.

[Justin]

Phil, correct me if I'm wrong, but aren't the large bearing seals just on the outside of the bearing? My recollection is that the roller bearings should be lubed by gear oil coming down the tube. Or did large bearing EBs not come with SET20 bearings?

[Viperwolf1]

Phil, correct me if I'm wrong, but aren't the large bearing seals just on the outside of the bearing? My recollection is that the roller bearings should be lubed by gear oil coming down the tube. Or did large bearing EBs not come with SET20 bearings?

The SET20 tapered bearings are not OE on early Broncos. The SET20 are the ones that use the axle oil lube and external seals. The original large bearings and seals are similar to the small bearing and inboard seal design but, of course, are slightly larger.

[Justin]

Thanks. Every big bearing 9" I've had has run the SET20s, so I'm not sure I've ever even seen the original bearings outside of a small bearing axle.

[BillsFan76]

I was trying to finish putting the drum brakes together and get the axle seals back in when I realize O'Reilly's gave me the wrong axle seals. Then I realize they also gave me 11" drums instead of the 10" I need. By the time I drive back there twice and got brakes and seals in it was getting dark. Didn't get to take the pumpkin out yet to see if anything is obvious. I'll get back on it Tuesday after work and post what I find. Thanks everyone.

[Gregg]

Once you have the center section out, there is a guy in Erie who is pretty good and has decent prices. There are a few of us that have used him. I brought him my center section with a 2 pinion limited slip and he put together a 4 pinion for me. It came to $350 ish. He has a lot of options and parts.

https://denver.craigslist.org/pts/5159273552.html

[BillsFan76]

Took a day off work today hoping to get this part of my mess finished and of course, it didn't work out that way :) I took my my axle to western drivetrain to have a new bearing pressed on and when the mechanic looked at it, he said the shaft had pitting at the end where seal was and that I should replace it because it would continue to leak.

He sent me to 4wheel parts saying they would have an axle for probably 125$ish. Not even close. Cheapest they had was $259 for the axle not counting bearing and labor to press it on. A mechanic walked by and looked at it and said he thought it was fine and sent me to another drivetrain shop. They said they would press it on but couldn't guarantee it wouldn't leak but the price to remove and put the new bearing on was only $70. Figured I would try that first and if it leaks I'll look for an oem axle or upgrade. Couldn't get it back till tomorrow though so back on hold.

Now for the 9" pumpkin. Finally got it out in my driveway with the help of my brother and this picture is what was laying inside bottom of the rear end. I almost crap my pants. I started turning the gears in the pumpkin though and everything looked intact. I took it to western drivetrain and had it inspected and tightened up. He said it had a lot of play in it but it was all intact and the pieces were from a previous rear end explosion. Threw it back in and filled it up with fluid. Just waiting on my axles and drums that still haven't showed up to put it back together. Hoping the axles seal fine and don't leak all over my new drums and brake hardware, fingers crossed. :)

[Justin]

That's wild! Previous owners never cease to amaze me. Bring your axles over. I'll press them on for free and might feed you beer. I'm in Lakewood, pm me if you're interested.

[BillsFan76]

If I hadn't left them at western drivetrain already I would have taken you up on it. Thank you for the offer. If the pitting in that passenger side axle does end up leaking, what do you think a used oem 9" axle will run me? The guys at 4wheel parts made it sound like it would be impossible to find and I should just buy their Yukons but i thought with so many people upgrading to beefier setups that it shouldn't be that hard.

[Justin]

Someone here probably has a spare. Heck, I might. Small or big bearing?

[Digger]

Yeah, see if anyone here has an axle for you first. 4 wheel parts is not the best source for technical expertise, especially compared to this place.

[Kinder]

Someone has a small bearing axle set laying around, driver or passenger side?

[Eck]

I will have some for a small bearing in a couple months if you have a slow leak or need some spares.

[BillsFan76]

Small bearing due to the 10" drum brakes and 28 spline if I'm understanding what I've been reading. Also, it's the passenger side.

[JGZ]

I've got a couple axles if you get in a pinch.

[Eck]

I think all the original axles were 28 spline but yes, small bearing came with 10" brakes while big bearing were 11" brakes.

[Justin]

Bummer. Turns out I've got 2 complete sets of EB axles, but both are big bearing. Guys, my recollection is that the wheel bearing ID for the BB axles is 1.5ish inches as compared to 1.375 or something for the small bearing ones. Is this correct? The axles can't interchange with different bearings, right? None of my axles are destined for anything they need to be functional for, so I'd swap yours for one if it worked.

[Viperwolf1]

I think all the original axles were 28 spline but yes, small bearing came with 10" brakes while big bearing were 11" brakes.

Here's the scoop on rear axles. All were originally 28 spline. There were 4 different rear axle sets for early Broncos. Small bearing/10" brake from '66-'75, big bearing/11"x1 3/4" brake from '66-'75, big bearing/10" brake from '74-'75, and big bearing/11"x2 1/4" brake from '76-'77. All had different lengths or brake offsets so it gets difficult to order new axles that fit if you are not 100% sure what you have. To help you identify your axles I have compiled a list of brake backing plate part numbers. These numbers are stamped on the outside (opposite of wheel side) of every rear brake backing plate. You don't have to remove anything other than dirt to read them. Each one is unique to the axle that goes with it. You can't mix and match the axles and backing plates and have it fit together correctly.

Bendix 319130L or 317363L = '66-'75 big bearing/11"x1 3/4" brake , driver side
Bendix 319130R or 317364R = '66-'75 big bearing/11"x1 3/4" brake , pass side
Wagner FF55264 = '66-'75 small bearing, 10" brake, driver side
Wagner FF55265 = '66-'75 small bearing, 10" brake, pass side
Bendix 80174L = '74-'75 big bearing/10" brake, driver side
Bendix 80175R = '74-'75 big bearing/10" brake, pass side
Bendix 3203097L = '76-'77 big bearing/11"x2 1/4" brake, driver side
Bendix 3203098R = '76-'77 big bearing/11"x2 1/4" brake, pass side