Steering U-Joint (ujoint)

[pitpawten]

Creating this thread since I didn't see this info in the forums anywhere.

When opening the passenger side knuckle we found needle bearings in the grease from where the ujoint had failed, not sure why.



Trying to source one was fun as most of the info is on driveline ujoints and the surplus supply is limited.

I found that the part were looking for made by Meritor and is part number CP750N. Note from the attached catalog (p130) that there are 5 versions of this joint with some oil bathed (as was the deuce with a knuckle full of grease) and some with a zerks (which seems to be the most commonly produced).

I was able to order up one of the greased style since that was what my local big truck supplier could get overnight, however I wonder what that will be like in the knuckle since it won't be able to pick up any of the grease that is in there. I'm contemplating prefilling it through the zerk and then removing the zerk and leaving it open so that some grease has the potential to make its way in (not sure how effective that will be)

So posting this here for when future people search and they now have a manufacturer and a part number to look it up as well as the dimensions from the attached catalog (p130)

 

[87cr250r]

I would put th zerk back on. With the correct grease, u-joints can easily go 100k+ miles between lubrication intervals. Grease will never work it's way in as centrifugal forces will tend to cause things to move outwards.

 

[pitpawten]

Grease will network its way in as centrifugal forces will tend to cause things to move outwards.

Yeah this makes sense, maybe I was just trying to justify spending over $100 on grease ; )

 

[cattlerepairman]

The extra grease lubricates the thrust washers and contact surfaces of the axle shaft. They do not seem to enjoy running dry.

Sent from my SM-G991W using Tapatalk

 

[pitpawten]

The extra grease lubricates the thrust washers and contact surfaces of the axle shaft. They do not seem to enjoy running dry.

Sent from my SM-G991W using Tapatalk

Yes absolutely and it can be easy to miss that since those washers can have the appearance of being a permanently attached part of the axle shaft rather than the (replaceable) washer that they are.

In fact I believe the TM calls for replacing them every time you do axle job if I remember correctly.

 

[cattlerepairman]

Unlocking the hubs helps a great deal with wear and tear in the front axle shaft area as well. The military solution of permanently locked in hubs , while soldier B proof, is not the most equipment-friendly.

 

[pitpawten]

Unlocking the hubs helps a great deal with wear and tear in the front axle shaft area as well. The military solution of permanently locked in hubs , while soldier B proof, is not the most equipment-friendly.

Yeah I've got a set of Selectro locking hubs on it from the previous owner so there's that

 

[pitpawten]

Just to close this loop I received my u-joint and it appears to be New Old stock with Rockwell branding on the box and stamped into the actual u-joint. It was actually missing two of the sea clips and there was some mild surface rest on the outside of the Caps which went away with a wire wheel but for which I got a slight discount.

I kept the older u-joint which still had all the caps as it seems like it shouldn't be impossible to rebuild it was the one of the lower retention rings that held in the needles which failed.

I'll just add it to the pile : )