The Stovebolt Site Forums The Shop Area Driveline Cork torque tube ball seal

My '49 keeps tearing these cork seals and I keep having them replaced. Is there a better replacement for this than cork ? Mine last less than maybe 100 miles...if that. Mine is an OEM five speed tranny but 235 motor from '57 car.

Are your engine mounts new? How about the mount at the torque tube ball? There shouldn't be a lot of movement of the ball unless you have loose mounts or are doing some rock crawling.
Is the ball and socket nice and smooth?
Did you follow closely the directions on shimming the ball prior to installing the cork gasket?
Carl

Thanks for the reply..I don't actually do this work myself but I'll fwd this to my wrench who does...Never knew about motor mounts and mount at the torque ball.

Last time this was replaced he said the ball was 'fairly smooth'...

The frame cross-member for the rear transmission mount might have been removed (used until 1954). It is not uncommon to find a truck with this cross member missing. It is needed.

Is the mating surface smooth where the cork slides on the ball?

Tim
Good information there ! Did not know that and will check. As for a replacement made of rubber and NOT cork, I looked at the McMaster-Carr web page under O Rings... Don't really know the size needed at the moment BUT I see that they will custom make an O ring for you for about $9.00. Needs to be I.D of more than 4" for them to make it..

So...what do you guys think ???

I have probably used 100 of the cork ones without seeing one break.

Uhhh...if that's so why have you used 100 of them ?

Don't under-estimate the sealing ability of cork, especially when soaked in fluid. It works better when it is installed dry and soon becomes saturated with the fluid. It expands a bit once this happens. Over use of sealants defeats the sealing ability of cork. For the toque tube ball, you would not want to use any sealant.
Carl

Carl,
I'm not underestimating the sealing ability, just the durability, at least in my truck... I go thru them so quickly. They are getting torn or broken by wear or vibration or...?

I'm about convinced to lay down the $$ and go with an open drive line.. Likely I should or will have to eventually...

Torque Tube U-Joint Ball Housing Adjustment Powerglide, Hydra-matic and manual shift trans. Ball Housing Adjustment are the same.

What it sounds like to me is the Wrench who does the work for you.
Might be not using the correct number of shims.
If the Ball Collar is to close to U-Joint Ball Housing it will tear the cork seal.
That's what the paper shims are for, to adjust how close or far the Ball Collar is from the U-Joint Ball Housing.

Note: The Powerglide and 1/2 ton Hydra-matic transmissions are the only torque tube drivelines
that use a separate stamp out piece metal to be used as the "Ball Seat".
The manual shift transmission ball seat is cast into it's tail housing.

Thanks... I'll pass this on to him..

You might want to Read This First.
Benefit of a torque tube driveline:
"You should mention about closed drive shafts is their absolute impervability to rear spring wind up" (Wheel Hop)

Thanks Jorb

I just read that.. It seems, at first and second glance, to lay fault on the rear ends geared in the 4:10/original range.. Mine had been changed to 3:55 a couple years ago

jorb,

I do not understand your distinction with regards to the presence of a "ball seat" in the various transmissions.

Any manual shift SM420 4-speed transmission could have a removable/interchangeably cast-iron rear-housing for an enclosed drive-shaft/u-joint "ball seat"; or, any SM420 could have a cast-iron rear-housing for an open drive-shaft/u-joint.

The cast-iron fitting/housing/cover ("tail housing" - rear housing?) on the rear of the SM420 transmission is interchangeable among all SM420 years. Any SM420 could be set-up for open driveshaft or closed driveshaft (with the appropriate rear housing).

This is very convenient.

Tim,

Let me re-word what I meant to say.
The very end of the tail housing on the Hydra-Matic and Powerglide transmissions is cast/shaped different,
than the very end of the tail housing on the 3 or 4 speed manual shift transmissions.
End of the HM tail housing
End of Manual Shift trans Fig. 22 and 23

In order for the U-Joint Ball Housing to fit properly onto the end of the tail housing of the Hydra-Matic and Powerglide transmissions.
GM stamped out a piece of metal (ball seat) which is placed on the end of it's tail housing. Ball Seat in Place,, Master Parts Catalog Group # 5.565 Seat
First the Rubber O Ring 1, Rubber O Ring 2 is placed into the grove, then the Ball seat.

Now the very end of the HM tail housing has the same shape as the tail housing end of the 3 or 4 speed manual shift transmission.
You could say the ball seat is cast right into the end of the tail housing of the 3 or 4 speed manual shift transmissions.
Therefore no need for a separate stamped out piece, for the 3 or 4 speed manual shift transmissions.

I really don't understand why GM didn't cast the ends of the HM & PG tail housings,
the same as the 3 or 4 speed manual shift tail housings.

Maybe I'm totally off base here (wouldn't be the first time), but I think we're talking about the cork seal that goes at the rear of the ball. The collar that holds the ball in place is adjusted by adding or removing paper (thin cardboard) shims. On the other end is the cork seal that that seals the rear of the ball to the front of the torque tube.

It sounds to me like the mechanic isn't using the two metal retainers that go on either side of the cork. It's a PITA to get it in there, but it seals pretty well. The two washers surround the cork and protect it. Without the washers the cork would be destroyed in no time. Is this the problem?

Never seen a problem with the cork piece that fits inside the collar. I guess you could tear it up if you put it in too tight, but seems questionable. When I redid mine I put a little gear lube on the facing surface of the cork and adjusted it by adding the cardboard gaskets before I reattached the U-joint. Check your shop manual, it tells how to do it. Then you'd know it was installed properly.

David,

I think the cork seal in this set is what is being discussed. The smaller rear seal that you are referring-to is the rubber seal that is inside the cork seal (in the illustration).

I have never used a cork seal in that location - maybe some sets provide a cork seal.

Yep, last one I did had a cork gasket in the rear. Only thing that I can imagine would tear up the front one is the ball surface being rough or warped in some way. Seems like that would be easy to see, though.

...cork seal...

...test...to many shims...


...seal with metal rings...

The OP = Original Poster "Dogface" of this Thread,
Did say' "Seal" {Needs to be I.D of more than 4",} in a earlier POST or as above.
So, it was the ball collar cork seal He was alluding to.
But, I have seen some Seal Kits that use a cork seal in the torque tube Retainer screw on ring. I prefer rubber.
I have not seen a rubber ball collar seal, only cork.

It could be a combination of both.
The ball collar is smooching the cork seal because of incorrect number of shims and a nicked up ball housing.

What is the best way to get the smaller cork gasket and rings inside the retainer ring?

Jackie

Jackie,

If this is what you are referring to, you have to open up the ball/bell/cover, slide it rearwards, and disconnect the u-joint.

Then, remove the rear yoke for the u-joint,
remove the seal/rings,
clean all parts/surfaces,
put the rear cap on/over torque-tube,
and put the tin-seal-ring in place.

Before to put anything back together, read and follow the instructions in the shop manual regarding how to determine how many paper sell-rings you need to seal the bell/ball/cover.

I am going back together with the driveline and have done everything you mention except the rear seal of the pivot ball assembly. The cork gasket seems to be a bit large for the threaded cap. I have the metal rings on each side of the gasket but cannot manage to get it to fit into the threaded part.

Jackie

In this forum a long time ago it was suggested that a national #327 o-ring, made of rubber would work. Dimensions are OD 2-1/8", ID 1-3/4", dia 3/16". Note that I have never used this but perhaps someone else has had experience with it. Don't know how rubber would handle 90W trans oil.

I finally managed to get the cork seal into the retainer, what a PITA. My fingers are now crossed hoping for only a tiny leak!

Jackie

The retainer oil seal should fit into the retainer cap without jamming it in.
The inside dimension of the oil seal is the most important.
That is where the seal makes contacts with the torque tube housing.
If you slide just the seal onto the torque tube housing and it is loose, you might not have correct size seal.
The I.D. of the seal should be the same as the O.D. of the torque tube housing.
You should also polish up the torque tube housing with emery cloth where the oil seal makes contact.

Check:
1929-1957 Chevrolet Master Parts & Accessories Catalog
Group # 5.469, Packing - Seal, Propeller and Pinion, Seal, oil, torque tube Dimensions

Something I don't see mentioned, and I've wondered this myself. I understand the two metal rings and the cork gasket between them on the rear retaining nut and their purpose. Would the tube need to be able to slide back and forth, (or in and out), to allow for flex? Same concept as the front yoke does on an open driveshaft. Or is the accommodated by the rear yoke inside the ball housing? The trans yoke bolts on, so it ain't moving. Logic tells me the rear yoke handles the flex. I have not looked in my shop/service manual yet, and this info is probably in there. Just asking from those that have done it.

Mike
1951 3100

Mike,

The u-joint cover housing/tube slides back and forth on the outside of the drive-shaft torque-tube (the cork/rubber ring/seal inside the metal rings, inside the rear of the u-joint housing/cover/ball/bell provides the oil seal), when the drive shaft moves in/out of the u-joint yoke.

You seem to have that figured-out right.

When the leaf springs compress and decompress.
I believe the torque tube and the rear axle moves front to back and back to front.

If you think about the fact that the front of the rear leaf springs are attached to the frame using one eye bolt.
The front of the leaf spring is just swiveling on that one eye bolt.

The back end of the rear leaf springs are attached to the frame using shackles.
When the springs compress and decompress the axle is moving slightly back and forth because of action of the shackle that uses two eye bolts.
It is swiveling on two points.
Photo of Rear leaf spring and Shackle

I understand that, (I round tracked for 10 years in a leaf spring car).

My concern was if the tube itself slid in and out, or if the rear u-joint yoke inside took care of that movement. I could not see how the yoke could if the tube was fixed solid. Tim says the tube moves, although I think very little, in and out of the ball housing. That makes sense. I mis-stated what I said earlier. Logic tells me the TUBE would have to slide, not the yoke, to accommodate the forward and reverse of the rear end during acceleration and slowing. Same concept as the front yoke does at the transmission on an open driveshaft.

The retaining nut, with the two metal washers and the cork gasket between them, needs to be snug enough to seal, but not so tight it puts the tube in a bind. Sound correct?

Mike

A1. You are correct that the Rear Yoke is attached to the tranny and cannot move back and forth.
The torque tube slides back and forth inside the U-Joint ball housing.
The propeller shaft slides back and forth inside the rear yoke.
Because both the torque tube and the propeller shaft are fastened & installed into the carrier housing.
They move back and forth together.
You could say everything in Illustration 1 moves back and forth.
And everything in Illustration 2 does not and is attached to the tranny.
Note: Manual, Hydramatic and Power Glide trannys share some of the same parts.
Propeller Shaft and Housing Illustration (Scroll down)
A2. When the retainer nut is tightened the oil seal is compressed which makes it bulge into the torque tube housing to make the seal.
No amount of snugness of the oil seal would bind the torque tube. The back and forth force is to great.
Just polish up the torque tube so it can slide easily on the oil seal.

Perfect.

I have me some ideas on this stuff, some are correct, and some are not correct. You and Tim have confirmed, what I thought was the correct way. And hopefully, for others who may have been wondering. (At least, I hope I'm not alone).

Mike

Many years back I bought a Fel-Pro gasket set (p/n ES72843) for that unit and it included rubber rings for both ends of the ball housing unit. I also have a set of cork rings. The larger rubber ring has a bevelled inside edge.

Hmmmmm..1688 views on this thread. Maybe I'm not by myself wondering...............

Thanks to all for the advice.

Mike

The other movement in the torque tube setup is the big rubber mounts between the axle and the center of leaf springs. I believe that this arrangement allows the pinion angle to be somewhat maintained over bumpy roads. Without these flexible mounts, undue stress would be transferred to the front of the torque tube as it slides in and out. Sort of a proper angle maintainer.
Carl

I keep coming back to it. Tackled mine for the 3rd time due to oil leaks. Got about a 95% improvement. Down to only a few drops after a drive. Wish there were an easy way to check the oil level. I can see what it leaves when parked but I have no idea how much if any I lose when driving. The transmission level does not seen to go down at all.