1962 GMC K1000 Dana 44 knuckle lube quantity

[Ledslinger]

Just finished rebuilding the Dana 44 in my 1962 K1000 Suburban and getting ready to fill with fluids. I bought knuckle lube from Torque King, and on their site it says to fill knuckle housing with 6 oz per side. Since the entire axle tube from the inner seal next to the carrier out to the spindle bushing has knuckle lube, shouldn't the long driver side take more lube than the passenger side?

I called them for clarification and was surprised they didn't really understand my 1962 Dana 44 front axle. They were thinking there was a seal and or a bushing sealing the drive shaft on the end of the axle tube and that the tube itself was dry. Not the case from my understanding and experience.

I'm just going to fill each side to near the bottom of the fill hole anyway, but I'm questioning if two tubes of 11 oz of grease will be enough. I'll probably just fill the short tube passenger side and if needed just put the rest in the driver side, then get another tube if needed.

Anybody verify the long axle tube side takes more than the short tube side? Know what amount goes in each side?

[72cs20]

The axle tube doesn't need any knuckle lube. The lube is for the spherical knuckle cavity.

If you had grease down the axle tube, it probably just migrated and accumulated there over the decades.

[Ledslinger]

How does knuckle lube not migrate toward the center section since there is a gap between the drive shaft and the opening it goes through on the axle end?

[Short 3/4]

Wow, great question.
I know for a fact the grease stays in the knuckle, but it’s been so long since I’ve had mine apart I can’t remember how. Dug up some old parts and looked in the factory manual and still can’t find the answer.
Someone please respond to this, as it’s really starting to bug me that I can’t remember this one
Tom

[Ledslinger]

In post #31 in this thread: https://www.ford-trucks.com/forums/1...rebuild-3.html

the ball on the axle tube outer end is shown, and the opening that accepts the drive shaft. Possibly the drive shaft just is close enough fit to the axle end opening that thick knuckle lube doesn't migrate toward the axle tube.

When I took mine apart after at least 45 years, both axle tubes had quite a bit of semi fluid grease in them. This is why I assumed the knuckle lube didn't stay just in the ball containing the drive shaft U joint. On my axle it didn't come from the center section as it wasn't gear lube. It had to have been filled from the knuckle fill ports.

[Short 3/4]

I thought the same thing about axel to tube clearance being close at the inboard end of the knuckle. Went out and looked at several axels in my spares pile and while they are nice and smooth at the pumpkin end where the seal rides, on the other end the casting is very rough, so no way oil would not migrate out of the knuckle. Keep in mind that most of us now use Cornhead grease or other thick lube in the knuckles, but according to the factory book they take 90W, just like the diff gears. If everything in the front end used the same lubricant there would be no need for the seal outboard of the differential. Look at how the HO rears are lubed. The same 90W lubes the diff and then runs down the tube and also lubricates the outer wheel bearings. Seams like they would have just done the same thing on the front end.
The more I think about this the more confused I get.

[Ledslinger]

Maybe the knuckle lube does migrate down the axle tube eventually, slowly and reluctantly. So with many services of the knuckle lube, eventully the axle tube gets a substantial amount in it.

My truck was 16 years old when I got it, and there was evidence the pinion had been out because one of the pinion shims was a valve spring shim. So if it went 10 years before the axle needed repair, then it spent 6 years of maybe getting the knuckle lube filled every oil change.

It is difficult to imagine that the knuckle lube may pretty much stay in the ball area. It could be that it mostly gets flung around in there but not out of that cavity.

The service interval for the axle U joints (as well as drive shaft U joints) is 1000 miles. Thats 50 top ups in 50K miles. If it lost a tablespoon down the axle tube in a thousand miles, 50 tablespoons is 25 ounces.

I think it loses some down the tube, and if it is replenished on schedule, a significant quantity can end up in the axle tube. I also think eventually the lube will be at the same level in the axle tube as in the knuckle housing.

[maxwoof]

My understanding is that the knuckle lube can flow through the axle tube to the pumpkin (but not into the pumpkin) and it’s also responsible for lubricating the wheel bearings. It will settle in the knuckle as it’s the lowest place, but going down the road and turning will cause it to move about. When I took mine apart, the wheel bearings were dry…the upper knuckle bearings were destroyed. When I put everything back together, I packed all the bearings with wheel bearing grease, including the u-joints, the same way you would pack any other bearings. And, I left the oil out. This has worked well for me, and I do drive the truck and take some highway trips. No leaks on the floor either.

[Ledslinger]

maxwoof - the knuckle lube does not lubricate the wheel bearings on a Dana 44. Knuckle lube doesn't go outboard of the bronze bushing in the spindle that supports the outer axle shaft.

[Short 3/4]

Bringing this one back to the top, as I’d also really like to know the answer to the original question. Notice several on this forum are in the process of restoring their closed 44’s, so maybe one of them could chime in.

Also, Torque King knuckle lube was mentioned. Anyone know the difference between it and the Cornhead grease a lot of us use.

Thanks
Tom

[Ledslinger]

No experience with corn head grease but I've read it thickens when the mechanism is stopped which helps minimize leaking when not running. When I filled my knuckle housings with the Torque King lube I sensed I'd seen a similar lube before. I suspect it may be Lubriplate 105 which is called both outboard grease and motor assembly lube.