Rear pinion seal change?

[vtach12]

Rear oinion is leaking pretty bad. I bought a sealed NOS seal. But now I was wondering if I would be better served by buying a new one from NAPA.

Also, Do I simply:
1. Drop the drive line
2. Pull the cotter pin and take off the 1 and 5/16" nut
3. Pull the shaft thingy out with a gear puller
4. Tear the old seal out
5. Pop the new seal in
6. Reinstall shaft, nut, and cotter pin

And if this is correct, how far do I tap the shaft thingy back in and how tight should the 1 and 5/15" nut be tightened? The gear oil in here lubs the wheel bearings too, right? (Not good to let run low)

Thanks, Jeff

[Gsmith]

You could spend the rest of your life trying but you'll never pull the shaft out. You need to pull the companion flange off of the shaft. You need a special seal puller to get that big seal out of there. That metal shell is pretty tough. The proper torque (by the manual) is 300 foot pounds for the nut.

[Gsmith]

Here's a picture of the puller

686-1.JPG Hope this helps.

[Charles Talbert]

Rear oinion is leaking pretty bad. I bought a sealed NOS seal. But now I was wondering if I would be better served by buying a new one from NAPA.

Also, Do I simply:
1. Drop the drive line
2. Pull the cotter pin and take off the 1 and 5/16" nut
3. Pull the shaft thingy out with a gear puller
4. Tear the old seal out
5. Pop the new seal in
6. Reinstall shaft, nut, and cotter pin

And if this is correct, how far do I tap the shaft thingy back in and how tight should the 1 and 5/15" nut be tightened? The gear oil in here lubs the wheel bearings too, right? (Not good to let run low)



Thanks, Jeff

An NOS seal is junk, it will still leak, don't waste time putting it in. You can't buy a new seal that will replace the entire NOS assy. We have an upgrade kit available if you are interested that comes with adapter, current production seal, & redi-sleeve that presses onto the flange to give the new seal a new surface to mate against. You can't tap the flange too far onto the pinion shaft, the nut torque is 300 FT. Lbs. with original 5.83 to 1 gearing. 160 ft. lbs. with 4.89 to 1 gearing. Forget just popping out the old seal, it's grown into the housing, or you will likely think so before it comes out. The seal puller mentioned in the manual for removing it is junk also, I have one, nice looking piece, only problem is it doesn't work. You will need to remove it with a pry bar or whatever you can get to work, many times they require heat for removal, still they can be tough.

NO the diff oil doesn't lube the wheel bearings. They have to be removed from the hub to be packed on a bearing packer or by hand.

Lunch break is over, let me know if I can be further help.

[MoparNorm]

Lunch break...that slapped me across the face Charles...I'd better get to work....= )

[Charles Talbert]

Lunch break...that slapped me across the face Charles...I'd better get to work....= )

Yea, does me that way everyday, the fastest hour of the day, lunch break.

[vtach12]

Charles,
How much for the new pinion seal and sleeve? Is it any harder to replace than NOS?

Well I have a spare front axel that I practiced on getting the pinion seal replaced on. I used a heavy seal remover and still can't get it out. The inner portion of the seal separated and popped out, but the reast is really stuck. (I am assuming that it can be removed without removing the shaft out the other end) I am ready to start drilling some holes and insert some bolts into it and trying to pry them out that way, any thoughts???

[Charles Talbert]

Remember what I said about being grown into the housing, now you have actual experience. It's whatever works for you on removal, it will pull out with force applied.

Our upgrade kit is $125 + $10 shipping. It includes an adapter machined from a solid piece of steel with threaded holes to mount a puller for removal if the need should arise. It uses a current production double lip seal installed into the adapter by us. The seal can be easily removed from the adapter for replacement if needed without pulling the adapter from the housing. The only reason the adapter would need to come out is for differential overhaul, gear / bearing replacement, etc. The Redi-sleeve (included with kit) has its own installation tool & easily presses onto the yoke seal surface so the new seal lips have a fresh, true mating surface. We have had zero problems to date where these kits have been used. Once we sell out the kits on the shelf, cost will increase because of increased machining cost on the adapters, probably around $10 per kit.

[vtach12]

Well, I had already purchased some NOS seals, and I am low on cash, so the NOS leather seal is going in for now.
I think the manuals stated to soak the whole seal in some kind of foot oil for 30 minutes prior to installation. Does anyone know the name of the oil and where it can be bought?

[Joel Watson]

Neets foot oil.

Hardware store should have it.

[vtach12]

Anyone remember the name of the oil?

[MoparNorm]

Joel posted the name, right above your post...= )

[Charles Talbert]

Well, I had already purchased some NOS seals, and I am low on cash, so the NOS leather seal is going in for now.
I think the manuals stated to soak the whole seal in some kind of foot oil for 30 minutes prior to installation. Does anyone know the name of the oil and where it can be bought?

Whatever, I was just giving you a heads up so you didn't have to spend time & money doing it twice, certainly your choice though. The NOS leather seals are the worst ones to leak & damage the yoke prematurely, there are some NOS rubber seals out there that do work better, but not like a current production seal will. Look out for this especially, if you see pits or a groove on the yoke seal mating surface when you pull it off the shaft, you may as well stop & not bother putting in any new seal. No matter what seal you use, NOS, current production, etc., it will still leak. The leather seals are notorious for cutting a groove on the yoke surface, so if you do have a good condition yoke now, it won't be good for long using a leather seal.

No need to go out & buy neatsfoot oil to soak the seal unless you just want too, any oil you have on hand, engine oil, gear lube, etc. will do just as well for you. Good luck.

[MoparNorm]

Good advice Charles,
Save money by buying the best part, one time, in lieu of the wrong part twice.
Maybe vtach can resell the NOS seal and save up for a better one...if the yoke isn't damaged.

[Nickathome]

Pinion seal

I used a slide hammer to get my seal out and it worked great. Drill 3 1/4" in holes around the outer circumference of the seal, tap them for a 1/4 X 20 bolt, then working from one hole to the next, drive the seal out. I read all the stories too about the seal having grown together with the diff. housing but in my case this just wasn't true. Mine came right out without too much difficulty, and all in one piece. I then used a 4" PVC end cap and rubber mallet to drive the new on back into place. This also worked great and cost pennies. You will however need a tool to hold the companion flange in order to get the big nut off. This tool too can be made for pennies from an old piece of flat steel.


Yes, you may have a heck of a time getting your old seal out, and then again you may not.