Lubing Universal Joints & Slide Yoke. Did I put to much it?

[NMuzj100]

I have always gotten the 1/4" of shaft extension w/ shiny steel showing but then I get a thin "ribbon" of grease exiting the same area all the way around the seal. Usually I get a few bubbles and a little water/grease emulsion first. I think this is the way it should work. I continue to pump until I see new grease. I am using an Amsoil #2 EP grease.

The Zerk is several inches from where the splines are sliding in the shaft so I don't think grease will get where it needs to with 1-2 pumps. I don't doubt that damage could result from a "grease locked " driveshaft but what I think is being described is seals that are sealing too tight to allow for proper lubrication. If the splines lack sufficient lubrication then they will transfer more load to the T-case when the rear suspension is being compressed as well.

There have been some comments in the grease forum on BITOG that the M1 grease is more "solid" than standard NGLI #2s and it may not "flow" as well through the grease seals on the slide yoke. Those who worry about compression problems might want to try a different grease as a low tech/low cost troubleshooting step. If the grease seals are already packed with junk then disassembly/cleaning sounds like a good idea to me.

On other forums I have seen a procedure for lubing where they jack up the frame until max driveshaft extension is reached. (showing a lot of shiny metal). They then pump the yoke full of grease. Then lower the frame slowly forcing the grease out of the seal as the shaft compresses but avoiding a shock through the drive train.

The "Rusty" area is the area of travel when the suspension is being compressed (heavy load or speedbump). The area where it travels under extension is the "shiny spot" and further up. (Great picture!)

 

[CameraCruiser]

NMuz,

Thanks for the comments and explanation of the rust colored area of the drive shaft. Since I was down there, I actually took an inch and half strip of fine emery cloth to the rusty areas and sanded the rust off. Only took a few seconds and then i followed it with about a 2000 grit cloth and applied a film of lube to the newly clean area.

The way I looked at it, was that it might as well slide back and forth along a smooth surface instead of the lightly rusted one.

With this light weight grit, I know that it only took the rust off, not the metal, well maybe a molecule or two, but nothing to out of round anything or affect the seals.

Thanks,

Rob

 

[IdahoDoug]

NMuz,

I agree with you that tight seals may be crudded up and require disassembly, but the jacking thing puts the exact same stress on TC components that continuing to force grease in does. So I would not recommend that if grease will not come out after a small amount of telescoping. Your seals seem to be working well/correctly.

DougM

 

[e9999]

NMuz,

I agree with you that tight seals may be crudded up and require disassembly, but the jacking thing puts the exact same stress on TC components that continuing to force grease in does. So I would not recommend that if grease will not come out after a small amount of telescoping. Your seals seem to be working well/correctly.

DougM

well, the thing with viscous fluids is that the force is related to the rate of deformation. I.e. you go faster you got more lbs of resistance. Similar to shocks (you can move them slowly, but try fast and it feels like a rock). So if you move the axle very slowly, you will generate much less force (on the TC say) than if you go fast over a bump on the freeway. So, moving the axle slowly, assuming it's not completely blocked, should be much safer than taking it for a spin with everything buttoned up.

 

[NMuzj100]

I think if you are not getting oil grease past the seal then 1-2 pumps will do you no good. You are simply filling the drive shaft cavity slowly and not getting the splines lubed. If the spines are not lubed then the TC will be getting stressed with every extension/compression cycle.

More coverage in another thread.

 

[5Cruiser]

Since this is in the FAQ, I thought I would link to another thread on the subject, which also links to other threads.

https://forum.ih8mud.com/100-series-cruisers/401590-official-clunk-thunk-driveshaft-thread-3.html

In reading both these threads this morning, it seems there are differing opinions...grease till it squirts, or just pump it once or twice and call it good. (now get your mind out of the gutter!)