front axle shaft and steering knuckle lube

[locomotive2101]

I know this subject has been discussed in depth but I still have questions from a lot of research. I know the front axle joints have been changed a lot from different manufacturers and different lube requirements based on year of manufacture of the vehicle. I wondered if anyone has real engineering data that describes why the different lube choices like the mb/gpw using chassis grease to most civilian using type O grease and later spicer joints specing 75w gear oil. Also and lastly, has any one ever thought of drilling and installing external grease fittings on the steering knuckle joints which are supposed to be lubed by the grease in the joint itself. I have building jeeps since the 1970s and I am still confused by what is really right and why. Thank you all for any real insight. P.S. I have been buying type O grease from Mowmore in 4.25 ounce pouches which are very nice to use and cheap. Thank you again and sty safe

[derekredmond]

It may not be as technical as you are looking for, but if you haven't seen it, I would recommend the article at https://CJ3B.info/Tech/SteeringKnuckles.html -- it does have some discussion of why the requirements of the various knuckles are different.

[binthere]

The reason that I use 140 gear oil is---If you fill the knuckle with grease, the joint will spin a hollow globe in the grease and not do it's job anymore. The other reason is that neither the top or bottom tapered axle bearing get any grease into the tapered bearing. And because they only rotate a small part of a circle they do not get grease all around. With 140 oil, when the hubs are in or the transfer case is shifted to 4-wheel even without the hubs in, the knuckle will splash the oil up into the upper axle bearing and the axle joint and lubricate everything.

[locomotive2111]

I am still doing research on the front axle closed knuckle lube.  As a rebuild mechanic in the Army I repaired hundreds of these on 2 1/2 and 5 ton trucks. Replacing the boots was a never ending job plus greasing the joints was no picnic. I just found a place that sells a grease for this very purpose. It is called Torque King 4x4 and the grease they sell comes in a caulking tube and costs $8.00 for a 16 ounce tube.  I did email Dana and asked them for any engineering data that was used in this design. On 2 1/2 and 5 ton trucks the king pins are lubed with a zerk fitting so that part of the joint is not concerned with splash lubrication from the joint.