Johnny Joint grease—an experiment

Only if you believe that can side load the snap ring too much.
I think the urethane 88 or whatever it is cannot exert the 100,000 psi required to pop that ring. I think it probably gives up around 8,000 psi, maybe 20,000 if you are an optimist and turns to goo. Either way, a far cry short of the pressure required to bust that snap ring. I am sure I am wrong and you will explain why but when I took apart mine today, read your comments that's the first thing that popped in my head. You have personally seen that what I am suggesting is correct, I think, but I don't mind hearing that I'm full of shit again.
 
I think the urethane 88 or whatever it is cannot exert the 100,000 psi required to pop that ring. I think it probably gives up around 8,000 psi, maybe 20,000 if you are an optimist and turns to goo. Either way, a far cry short of the pressure required to bust that snap ring. I am sure I am wrong and you will explain why but when I took apart mine today, read your comments that's the first thing that popped in my head. You have personally seen that what I am suggesting is correct, I think, but I don't mind hearing that I'm full of shit again.
Just curious where you're referencing the 100,000 psi from? Got a chart, book, or something? Might be handy to have on hand in the future
 
Hardened steel, which I think the forged housings are made of. I read 110,000 and rounded down. The key here is metal is stronger than plastic. Charts, books, links on the web, get a book that smells like mildew and trust that and not me. Not me.
 
so now we are at the outside of the bushing halves should stay clean their job is to keep a snug grip in that casing. it's the balls job to move inside the bushing. so the outside being kept clean will not have any slip aid that could lead to easing the ability to rotate or shift those bushings around in that casing under stress?
 
I think the urethane 88 or whatever it is cannot exert the 100,000 psi required to pop that ring. I think it probably gives up around 8,000 psi, maybe 20,000 if you are an optimist and turns to goo. Either way, a far cry short of the pressure required to bust that snap ring. I am sure I am wrong and you will explain why but when I took apart mine today, read your comments that's the first thing that popped in my head. You have personally seen that what I am suggesting is correct, I think, but I don't mind hearing that I'm full of shit again.
The ring is good for 15,500 pounds of load. I doubt that the outer edge of the groove will get even close to that.

What I know beyond a shadow of a doubt is the rating for any rod end is far lower axially than radially. A simple example is one of the Aurora sphericals we would use in something like a shock eye. Static radial is 9400 lbs. Static axial is 1400. That is a significant difference.

All anyone has to do to prove me wrong which I am fully okay with is put a JJ in a press that shows tonnage and show the difference in lubricated shell inner walls and not lubrication with an axial load test.
 
Hardened steel, which I think the forged housings are made of. I read 110,000 and rounded down. The key here is metal is stronger than plastic. Charts, books, links on the web, get a book that smells like mildew and trust that and not me. Not me.
100K or 100Kpsi? If it is the latter, then you have to calculate the cross sectional area of the lip holding in the retaining ring.
You are correct on them being a forging.

Which is stronger, oil or steel?
 
so now we are at the outside of the bushing halves should stay clean their job is to keep a snug grip in that casing. it's the balls job to move inside the bushing. so the outside being kept clean will not have any slip aid that could lead to easing the ability to rotate or shift those bushings around in that casing under stress?
My concern, unfounded or not is that lube inside the shell between the races and shell inner wall can increase the thrust load on the snap ring.
 
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Which is stronger, oil or steel?
This is a very good point, when I look at these high impact forces I consider most plastic moving just like a fluid, maybe that's a mistake. Possibly the bushing can flow around the ball and even exit the housing at the forces that might be needed to deform the washer or snap ring groove? Not worth busting joints either way, your point about keeping the barrel dry is a good one.
 
This is a very good point, when I look at these high impact forces I consider most plastic moving just like a fluid, maybe that's a mistake. Possibly the bushing can flow around the ball and even exit the housing at the forces that might be needed to deform the washer or snap ring groove? Not worth busting joints either way, your point about keeping the barrel dry is a good one.
All I actually know is lubing between the race and the shell bore wall can NOT possibly lessen the thrust load on the snap ring. It may be the same, it may be higher but there is no way I can conceivably make it be less.
 
I rebuilt all my rear johnny joints yesterday. These were done once already this year, in May. Couple wheelin trips and this is what they looked like...

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The grease is a solid. Its also been displaced out of the joint, so the place where the ball rides was dry. The net result? My jeep creaks and groans over bumps like a room full of 40 year old "dads."

Once you dip the parts into a tank of simple green the grease transforms. It becomes a snotty, sticky mess. Its gross. Can't brush it off, it just slides around. It needs to be wiped off with a disposable rag (many disposable rags). Anyway, I cleaned them all off again and lubed em up with the energy suspension stuff. As a secondary experiment...On the front I just put enough grease in to cover the "race". On the rear I placed much more grease in. Enough so that it squeezed out the grooves in the race and made a collar of sorts around the ball. The theory I'm testing is if the grease will create a barrier toward water intrusion.

I really hope this stuff works...rebuilding these joints after every wheeling trip will get OLD.
 
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I rebuilt all my rear johnny joints yesterday. These were done once already this year, in May. Couple wheelin trips and this is what they looked like...

View attachment 279460

View attachment 279461

The grease is a solid. Its also been displaced out of the joint, so the place where the ball rides was dry. The net result? My jeep creaks and groans over bumps like a room full of 40 year old "dads."

Once you dip the parts into a tank of simple green the grease transforms. It becomes a snotty, sticky mess. Its gross. Can't brush it off, it just slides around. It needs to be wiped off with a disposable rag (many disposable rags). Anyway, I cleaned them all off again and lubed em up with the energy suspension stuff. As a secondary experiment...On the front I just put enough grease in to cover the "race". On the rear I placed much more grease in. Enough so that it squeezed out the grooves in the race and made a collar of sorts around the ball. The theory I'm testing is if the grease will create a barrier toward water intrusion.

I really hope this stuff works...rebuilding these joints after every wheeling trip will get OLD.
Not that I expect you to miss it but a lot of folks do. There is a long side and a short side to the ball. Done that way to have the same amount of bolt sleeve sticking out past the joint body.
 
I rebuilt all my rear johnny joints yesterday. These were done once already this year, in May. Couple wheelin trips and this is what they looked like...

View attachment 279460

View attachment 279461

The grease is a solid. Its also been displaced out of the joint, so the place where the ball rides was dry. The net result? My jeep creaks and groans over bumps like a room full of 40 year old "dads."

Once you dip the parts into a tank of simple green the grease transforms. It becomes a snotty, sticky mess. Its gross. Can't brush it off, it just slides around. It needs to be wiped off with a disposable rag (many disposable rags). Anyway, I cleaned them all off again and lubed em up with the energy suspension stuff. As a secondary experiment...On the front I just put enough grease in to cover the "race". On the rear I placed much more grease in. Enough so that it squeezed out the grooves in the race and made a collar of sorts around the ball. The theory I'm testing is if the grease will create a barrier toward water intrusion.

I really hope this stuff works...rebuilding these joints after every wheeling trip will get OLD.
Mike, I appreciate you posting real world midwest experience!
 
Not that I expect you to miss it but a lot of folks do. There is a long side and a short side to the ball. Done that way to have the same amount of bolt sleeve sticking out past the joint body.
^^ Almost all the balls on my rig have a small line around the collar on the bolt sleeve on one side. That side goes toward the side with the snap ring.
 
^^ Almost all the balls on my rig have a small line around the collar on the bolt sleeve on one side. That side goes toward the side with the snap ring.
They haven't always had that ring to tell you. We just got in the habit of marking them. Doesn't matter how you do it, just be aware it needs to be done.
 
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So, Does the long side of the ball go on the snap ring side? I redid the uppers over the winter. And now that its mentioned , I remember the sides being different. But thats it..until now.
 
So, Does the long side of the ball go on the snap ring side? I redid the uppers over the winter. And now that its mentioned , I remember the sides being different. But thats it..until now.
Long side goes on the snap ring side due to the extra bit of depth needed to add the snap ring and groove for it. The other side doesn't have a snap ring, just the lip for the washer.