The Stovebolt Site Forums The Shop Area Driveline Driveline leak

Hey guys,
Every day I have this leak on my garage floor pan. There is about a quarter size leak that I wipe up every day. I took this picture from under the cab that comes from the coupling in the drive line/torque tube. I'm pretty sure it's gear oil.
Anybody have an idea where it might originate from or how to stop the leak?

There's a cork seal ring under that nut. You can try tightening the nut to see if it slows down, or there are reseal kits for the u-joint ball, but you have to pull the whole thing off the end of the driveshaft to replace it. It's not a real easy job, as you have to either jack the torque tube up above the transmission housing (assuming there's enough room between it and the cab floor or drop the transmission mount crossmember (you might not have one on a '53) to drop the torque tube below the transmission. You also have to select the number of gaskets that go between the transmission and ball housing before installing the cork seal at the ball. The service manual covers the procedure.
I would try snugging up the nut first. That might slow it down to a smaller drip. You also need to be sure that the u-joint housing is filled with gear oil thru a side plug near the rear. If it stops leaking by itself, that means the u-joint isn't being lubricated and might blow up on you.

Tighten the collar tight and cross your fingers that this works. Most collars have already been tighten to the limit. There is a seal behind the collar that is squeezed by two rings when you tighten the collar. You can replace the seal but it may quickly wear out if the ball joint is stuck.

There are tons of previous discussions that you can read to educate yourself. Like this one:

https://www.stovebolt.com/ubbthreads/ubbthreads.php/ubb/showflat/Number/604759

Guys thanks for the responses. Can I just attempt to tighten that nut with a pair of channel locks?

Yes
Channel-locks work.
Don't forget to check your tranny gear oil level.

Okay perfect. I'll report back and let you all know what I find.

Get a piece of square rubber O ring material and cut it at a 45 degree angle, then wrap it tight around the torque tube and trim it to fit. Super glue the ends together. Then tighten the gland nut. No need to dismantle anything.
Jerry

Jerry would you happen to have a picture? I'm not sure I'm totally following you. I'm willing to try though

No, but I'll be glad to have a 2 way conversation by email or PM. It's pretty simple to make an O ring from bulk material, either round or square stock. Just cut the material to fit the part and glue the ends together after you wrap it around the torque tube, then tighten the gland nut. You get a better bond on the glue joint with an angle cut. Send me a PM and I'll respond with an email address and/or a phone number. I've been making special sized O rings that way for over 40 years.

For instance:

www.ebay.com/itm/254184004632?

Jerry

A quarter size drop? You're on easy street!

Jerry, would silicone sealant or RTV gasket maker work there?

Try a rubber ring from a oil filter they are square I will take a look as I have my tube ball off the truck and get you a few pictures.

Please refresh my memory, is there a seperate fill plug for the ball joint and transmission? I thought after the Initial ball joint fill that the transmission fluid kept the ball joint filled. Thanks.

There is an O-ring that may help. I have not used it but I believe it was mentioned in this forum a while back. P/N National 327, outside diameter 2-1/8" inside diameter 1-3/4" thickness 3/16". Hope that helps. Ed

In case anyone missed the link, the manual is available and it's free.
Adding lubricant is mentioned here:
http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0713.htm

Here are some pictures ,papa 52 there is a small plug to fill the ball and a plug on the side of the tranny,mine is a sm420.you can see the small pug in the picture.the gaskets to the left are old oil filter gaskets you would need two to make up the thickness of the origional.the origional looks to be a combo of different material .

THANKS! Will check.

Not unless you have some way to mold it into a perfect circle the proper diameter and thickness. Then it would still have to be cut and spliced unless you're going to disassemble the ball joint.

I've seen attempts made to replace that seal with the graphite-impregnated string used for water pump packing, usually unsuccessfully.
Jerry

Here's another possibility- - - - -put the joint at the top so the seal prevents a seep leak at the bottom. 6MM or maybe 8MM should be about right. 1 meter (3 feet) should be a lifetime supply.

www.ebay.com/itm/144002221038?

Jerry

This is what I am referring to. The only way I see to access the ball joint plug is from the top thru the hump cover.

The ball joint fill plug should be accessible from underneath, using a lube pump. Too close to the cab floor to be able to pour from a bottle. There's a bearing separating the rear extension of the transmission from the main body. The shop manual calls for 1-1/2 pints in the transmission itself and 1/2 pint in the rear extension for the u-joint, so 1 quart should do the whole thing, assuming you don't spill any.

Jerry's idea of a square section rubber ring is spot on. I may even replace the new cork/rubber packing ring that comes with the repair kit in mine, as I haven't installed it yet.

Thanks.

All the pictures are surely helpful! Thanks guys.

I was not able to tighten the nut any further, so I'll order some square gasket material and hopefully able to stop the leak that way.

Doug, to make sure you understand, the seal is made of cork or cork-like material. The attached picture shows the seal and collar being moved into place for tightening. The area were the man's left hand is the tube. It moves in and out (axial movement) as the rear axle moves (acceleration, braking etc.). His right hand is on the ball. The ball and it's neighbor parts are made to pivot (angular movement) as the rear axle moves (taking a curve, hitting a pot hole etc.).

Thick cork was/is used to keep the lubricant from flowing out yet allow movement. Cork is porous and a little of the lubricant will leak through. Infrequent dripping is good. As cork ages it become brittle. It can crumble.

Just for safety. The torque tube can be under tension of weight and the energy in the rear axle leaf springs. If you try to remove the U-joint, the tube can crack your head. Always support the torque tube.

I for one would like to hear your results with the square gasket material.

The cut & glue trick was a common flat rate shortcut, back when mechanics routinely squeezed 60 hours' or more labor time into a 40 hour work week. It turned an hour's worth of work into 15 minutes or so, and if the diagonal cut stayed at the top of the tube- - - - -I've never seen oil run uphill!
Jerry

When the collar is removed the drive shaft stays in position, correct?

Which way do you make the diagonal joint? Cut longitudinally or cut laterally?

In other words, are the long points of the cut on the faces of the seal or on the OD and ID?

Could be either, but would be easier OD and ID.

Buoymaker, that is a terrific explanation! I'm a visual guy, so pictures sure help! I was originally confused about having to drop the whole driveline to replace the cork. I get that now, as the cork o-ring is a solid piece that would have to fit around the torque tube. By using Jerry's method, now I can just loosen the collared nut and put the square gasket material as it can be spliced back together. I ordered some square gasket material last night. I probably won't be able to attempt the fix until after the holidays are over. But I will surely report back with some pictures as well to help anybody else.

I'd overlap the angled cut from side to side, like angling from the driver's side to the passenger's side of the seal material. Then the flat washers on both sides of the seal will squeeze the lap joint together. A drop of super glue on the angle joint will hold everything in place during reassembly. Once us oldtimers start pushing up daisies, let's hope some of us will be able to pass on a little of that hard-earned knowledge first!
Jerry

That makes sense.

Us newcomers are listening, and appreciate you “old timers” knowledge. 👍