The Stovebolt Site Forums The Shop Area Driveline Help: leaking rear Rear Oil Seal

Hey All, need a little preadvice on my leaking axle in my stock '51 Chevy 3600 3/4 ton with stock rear end, I broke a brake line the other day moving it to get it going well after 20+ years of ingnoring it and am waiting on the preformed brake line kit, but the LR rim has some leaking on it (photo) I got the drum off with some penatrating oil, brake backing off and some tap-tap-tap. But I see that the wheel cyclinder is dry it seams on primary inspection this am, esp looking at the backing plate, I see that it's wet below the axle So seems like the oil seal needs attention.

Looking at my Manual and it's pretty detailed in instructions, I see that I need to pull the 8 bolts off the end of the axel and pull the axel out, I then need to pull off the Wheel Hub, I see that I maybe need a special tool to pull the outside nuts and adjusting nuts (is this true). The hub contains the wheel bearings and inside that -the oil seal. The Hub will have to come off to get at the axle seal just inside the bearings.

I'm going to attack this Monday and Tues. But I see in my manual that I need special chevy tools etc...

Questions:
Can I get the nuts off on the outside to remove the Hub with common tools, snap ring plyers etc...
Can I pull the oil seal out, with the Hub, off from the inside of it without pulling the bearings if I find it hard to press out these bearings/races?
Where can I buy these seals? And bearings if I need them?

Any general advice full appreciated before I go at this this week. Fingers crossed. And thanks
-Clem

You just pull the axle bolts off the end, slide axle out and you will see a big nut with a lock tab on it I believe. Tweak that out and its as simple as tapping that nut with a punch or screwdriver and hammer. There will be a lock ring under that then another nut against the bearing. Once thats off the entire hub and bearings pop right off and you can pry the seal out and do whatever you like with the bearings as far as cleaning , checking, or just pop them back in with a new inner seal. The outer seal is the actual axle flange gasket and/or rtv. I haven’t had mine apart in a while so the type of lock ring is fuzzy in my memory but it’s generally the same type of setup in almost any full floater rear that I’ve had apart. Pretty simple to work on once you do one or two.

I've made those spanner nut tools from pieces of square key stock welded to a piece of pipe for many years. A professional parts store like NAPA will have the correct socket, but untold thousands of those nuts have been removed and installed with hammers and punches since those trucks were new. Be careful with the washer that's sandwiched between the nuts with locking tabs that secure both nuts by bending them down- - - -if you take it easy straightening the tabs so the nuts will turn, they're usually reusable.
Jerry

Regarding the bearings: The inner bearing inspection is simple. The cone just falls out once you remove the seal. The outer bearing is a different matter. I see that you have the manual so read it carefully. But as I recall it is not entirely clear. I did this recently. Here's what I remember: It turns out that it's a good deal easier and more stable with the drum attached to the hub.

First remove the inner bearing cup (outer race). 2) Using a hammer and suitable punch knock the outer bearing cup away from the snap ring just enough to release it from the ring. 3) With a STOUT pair of snap ring pliers, remove the snap ring through the inner bearing-cup seat. 4) flip the whole affair over and with a smallish punch that will fit through the axle-cap bolt holes find the cutaways in the hub casting giving access to the back of the cup. Not every bolt hole will line up so experiment al little till you find three that do at 120 degree intervals. 5) tap the bearing cup out of its seat and the bearing assembly will fall through the hub onto the bench.

Inspect the bearing. Finding it to be OK, reverse the above procedure. Once the outer bearing cup is retained by the snap ring, knock the cup against the snap ring to the bearing adjustment won't change under tension.

The original barrel-roller bearings are no longer available but tapered rollers work just fine. They are not necessarily better.

As usual, the second one should go much faster.

Note that the hub is designed with a shield on the inner side to duct any leaking oil out to the back side of the wheel not into the brake. If you don't clean this out, oil will continue to leak out of the shield onto back side of the wheel and you will think it's leaking again.

Once the hub and bearings are reassembled, jack up the opposite wheel so the axle tube is tilted pretty noticeably. If the rear end grease is at the proper level, it will run down the axle tube and lubricate the bearings. If this isn't done, and the hub has been assembled dry, the weight of the vehicle on the dry bearing can damage it before the lube works its way down the axle tube.
Jerry

Hi Clem,

Do yourself, and the next person to work on that axle a favor by buying or borrowing the correct socket to remove/reinstall the bearing retainer nuts. Yes, other tools like punches will work, but you do run the risk of damaging the nut or the axle tube threads. The person who serviced the axles previously on my truck used a chisel. Not a pretty site when I went in there the first time to service the bearings.

As Jerry mentioned, you can get them at the larger chains like NAPA.

They are also all over the online auction sites, too. There are different types, so the trick is trying to determine the correct one for your application. Perhaps someone on this site has one that is known to work, and can provide the model number.

Best Regards...

Thanks all, I got the axle out easily yest just before dark. I'm off to Napa today and will get axle gaskets and seals. Will ask also about the socket also. I would imagine this is a special order issue but excited to get this sorted out.
- Clem

Keep your eyes out, one can never tell what one sees laying around. I found a axle nut wrench for my GMC 630 big truck, laying around with some other junk, do like Bob says, get the proper tool, then you can loan it out to get exchange labor for heavy lifting.

Ed

Hey all, the axle came off easy actually - without the socket (didnt have it at Napa San Rafael-but they had oil seals and axle gaskets!). So with a punch, the bolts and tab/locking washer bent out of the way, it all came off easy, the seal looks fine but Im sure this is leaking since its oil on my rim, not brake fluid and my WC looks dry on the rubber ends. With the axle hub out, I can get a heavy duty but thinner wide motorcycle tire removal tool under the oil seal and hitting it pretty hard down on the otherside, trying to leverage/pry it up, it wont budge, not a little. I'm a little worried to pry on the bearing. Do folks know if this is a good bad idea. They are prob crazy strong but with focused force, dont want to ruin it. Is this ok with a big flat screwdriver? While trying to do the hitting backside leverage thing - I also put a little square stock on the rim of the axle, in case I made some headway-so that I dont press down the seal towards the bearing, but still no luck. Any ideas, might have to go to a pro car guy friend and use his press and do the whole axle hub.
-clem

The seal is toast anyway. Drill a small hole in it and put a good sized sheet metal screw into the hole. Then use a claw hammer or a carpenter's wrecking bar to pry the seal out. Be sure not to drive the screw in where it messes up the part number- - - -your parts guy might need to cross-reference it. That's an old 18-wheeler seal trick.
Jerry

That seal removes from the back side of the flange. Remove the 5 bolts that retain the flange & the flange should come off. Then you can replace the seal in the flange. It only fits one way.
There is a thick cork gasket that goes between the flange & housing. If you can't get one RTV will work.
George

Hey All

Got it out this am!! I tried something different and it went well. I put the axle hub on a pair of 2x4s to raise it up, then I put it seal side down and slid in the end of a 4" long piece of 1" wide thinner steel plate. I put it above the seal and in front of the bearing (since the Inside Diameter of the bearing is smaller than the seal - I cant see the seal from above), and the other end of the steel plate rested on the ground I think only had to hit on the steel plate 5-10 times and the seal moved, I kept rotating the hub between the 2x4s and it easily popped the seal out, no issues. Cleaned it up, checked the bearings and they are the original roller type, packed them again, and put everything back in. I also added some permatex to the oil seal OD as it said in the manual, tightened up the two nuts on the outside to seat everything, and backed it of 1/8 turn, locking washer and top locking nut and everything bent to hold it all in place, I also added some permatex to the axle hub metal gasket as I slide in the axle. Now, Only need top up the oil level, adjust the brakes, and put this axle side downhill overnight to soak the bearings prior to running around and it all should be good. Fingers crossed the leak is gone. Hopefully so.

Thanks all for ideas and support. All if helped and glad I'm not dirtying up the rim anymore hopefully
- Clem