Dana 44 Closed Knuckle Axle Shaft U-Joint Part Number

[jeffahart]

Originally Posted by Chaparralman1974

Ok, so I ordered the new ujoints for the axle shafts. The original ujoints did not have the seal on them as it is all lubricated from the special sauce that lives in the knuckle cavity. The new ujoints have the seals on them. Do I have to remove the seals, or just let the permalube idea take care of itself?

Funny the things that make you scratch your head.
Here's my take, I'd leave them on. They're more than just dust caps. Think of it this way. I used to have an old paint brush spinner. I would stick the brush handle in it and stick in a empty buck and it would spinn the excess paint off the bush bristles.

If you stuck a joint without the seal, let's say a driveshaft. It would be exposed to dirt sand and the likes. But.. would it spin the grease out of the joint trunnion?

If it's inside, will it take on grease, or lose grease, or neither.

For me, the low hanging fruit is leave the part as shipped and install it.

Good luck; and have fun!

j

[Chaparralman1974]

Originally Posted by jeffahart

Funny the things that make you scratch your head.
Here's my take, I'd leave them on. They're more than just dust caps. Think of it this way. I used to have an old paint brush spinner. I would stick the brush handle in it and stick in a empty buck and it would spinn the excess paint off the bush bristles.

If you stuck a joint without the seal, let's say a driveshaft. It would be exposed to dirt sand and the likes. But.. would it spin the grease out of the joint trunnion?

If it's inside, will it take on grease, or lose grease, or neither.

For me, the low hanging fruit is leave the part as shipped and install it.

Good luck; and have fun!

j

That is what I was kinda thinking as well. It would seem that the dust seal supercedes the old design. I think I will leave them on and then still fill the void with corn head grease. Probably a useless gesture, but I am having fun with it. Hell, what is the worse thing that can happen? LOL

[jeffahart]

Originally Posted by Chaparralman1974

That is what I was kinda thinking as well. It would seem that the dust seal supercedes the old design. I think I will leave them on and then still fill the void with corn head grease. Probably a useless gesture, but I am having fun with it. Hell, what is the worse thing that can happen? LOL

Don't sweat the small stuff! I filled my worm gear winch with corn head grease. Love the stuff! I wouldn't put corn head in any cavity where there is grease or supposed to be greasee. It's used in lieu or oil... as it liquifies when heated up.

j

[Short 3/4]

So sounds like you’ve decided to keep the closed knuckle for now? I’m guessing you’ll be very happy with it when you’re done, and if not you can always throw in that newer one later

As far as the seals on the U joints you would probably be fine either way, but yea I think leaving them on is the best way to go. That same joint will last many thousands of miles in the environmental hell of an open knuckle, so enclosed in a nice clean closed knuckle it will last many times longer. Just like every other mechanical system on our trucks, the only thing that will kill a part is too much horsepower or not enough clean lubrication.

Don’t think that you don’t have to worry about keeping the lube topped up in the knuckle though. Remember that’s the only thing lubricating the upper and lower bearings. I also love the Corn Head grease. Never could keep 90W in those things.

Tom

[Chaparralman1974]

Originally Posted by Short 3/4

So sounds like you’ve decided to keep the closed knuckle for now? I’m guessing you’ll be very happy with it when you’re done, and if not you can always throw in that newer one later

As far as the seals on the U joints you would probably be fine either way, but yea I think leaving them on is the best way to go. That same joint will last many thousands of miles in the environmental hell of an open knuckle, so enclosed in a nice clean closed knuckle it will last many times longer. Just like every other mechanical system on our trucks, the only thing that will kill a part is too much horsepower or not enough clean lubrication.

Don’t think that you don’t have to worry about keeping the lube topped up in the knuckle though. Remember that’s the only thing lubricating the upper and lower bearings. I also love the Corn Head grease. Never could keep 90W in those things.

Tom

Hi Tom!

Yeah, the more that I pondered on it, the more that I wanted to keep the truck original. I had the drums checked out and they were ok to turn. Also the price to get new drum brakes was considerably less than a full disc brake conversion. Lastly, using the original axle I don't have the mess with regearing anything. So, for now I am going to stay with the original axle. If I decide to change later on down the road, I can alway swap in the closed knuckle. This will also allow me to to spend money on other parts of the restoration that are more important at the moment.

Clay

[Short 3/4]

Well now you guys have me (over?) thinking about this whole seal or no seal thing. While I still stand by my original thought that it probably doesn’t matter either way, Jeff brought up a really interesting theory. It all made sense until I realized that the knuckle fill hole is about at the center of the axle shaft, so the analogy would be more like constantly dipping the paint brush into a can of paint, not spinning it dry. This would force grease in with every rotation.

While I don’t have access to part numbers to prove it, I’m thinking that the same u joint is used for both open and closed knuckles and you simply leave the seal on for open (to retain grease) and remove it for closed (to replenish the grease). It makes sense to me, but if not the case, please let me know as I’m here to learn, not preach.

On another subject, I hope you know to replace the oil seals just outboard of the pumpkin. It’s a real PITA but needs to be done while you’re in there, as they are probably original and will cause no end of problems if they start leaking.

Keep up the great work
Tom

[Chaparralman1974]

Originally Posted by Short 3/4

Well now you guys have me (over?) thinking about this whole seal or no seal thing. While I still stand by my original thought that it probably doesn’t matter either way, Jeff brought up a really interesting theory. It all made sense until I realized that the knuckle fill hole is about at the center of the axle shaft, so the analogy would be more like constantly dipping the paint brush into a can of paint, not spinning it dry. This would force grease in with every rotation.

While I don’t have access to part numbers to prove it, I’m thinking that the same u joint is used for both open and closed knuckles and you simply leave the seal on for open (to retain grease) and remove it for closed (to replenish the grease). It makes sense to me, but if not the case, please let me know as I’m here to learn, not preach.

On another subject, I hope you know to replace the oil seals just outboard of the pumpkin. It’s a real PITA but needs to be done while you’re in there, as they are probably original and will cause no end of problems if they start leaking.

Keep up the great work
Tom

Hmm.....now I am rethinking it as well. I don't think it can hurt either way really. If the seals are left off, then it should recieve lubrication as long as the knuckle cavity is full. With the seals on, it never needs lubrication (just like the ones that are in drive lines and such any more). I am tending towards just leaving the seals on and using the lubricant in the joint to keep the knuckle bearings lubricated if anything.

Yeah, I am replacing the inner axle seals. I pulled the carrier out the other day and noticed that the seals were crumbling apart. The nice thing about the older carrier setups is that the shims are between the carrier and the bearing and not the bearing and the housing. So reassembly will be a piece of cake. I would imagine that initial setup for preload and backlash would be a pain though.

Clay