Question about replacing driveshaft u-joint

mgroeger

mgroeger

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I've been getting a whistling bird singing noise from the rear diff area where the drive shaft enters it. I was told to check out the U joint and sure enough the races are pretty scared.
I bought a grease less (lifetime grease) joint from Spycer and installed it (youtube'd it to make sure)
The one thing I noticed is that it's pretty stiff to rotate. I put the caps on just enough to get the clips in and that really snugged thing up. The video did say that this can happen and to tap the yoke with a hammer to free things up and also to take a large flat punch and tap the end caps. Tapping the end caps made it tighter but after hitting the yoke a few times it moves all be it kind of stiff.
I've never replaced one before so I don't know hwo stiff it should be. I am able to take one hand and grab the exposed ends caps and swivel the joint without too much difficulty.
 
It should feel snug, but not tight or stiff. When replacing u joints I usually will do a short, forceful tap on each cap without the clips in to free things up. Light taps only made it stiffer in my experience.
 
Well it's VERY snug, is what it is at this point. Yeah I don't quite understand how tapping the caps like that frees it up because if I tapped it without the clips in it would have moved the opposite cap to the point where I couldn't put the clip back in. I guess that's why the video said do it with the clips in, regardless what helped mine was to tap the yoke with a good pop. Everything is assembled and looks/feels good.
What I noticed was the one cap had to be hit harder than the other and also I couldn't get the clip in so I had to keep tapping that cap on little by little until I could gt the clip in and obviously with every tap it snugged up.
I'm probably just OCDing this but it was snug. Time will tell at this point. My understanding that if it is too tight it will wear out prematurely.
 
mgroeger said:
Well it's VERY snug, is what it is at this point. Yeah I don't quite understand how tapping the caps like that frees it up because if I tapped it without the clips in it would have moved the opposite cap to the point where I couldn't put the clip back in. I guess that's why the video said do it with the clips in, regardless what helped mine was to tap the yoke with a good pop. Everything is assembled and looks/feels good.
What I noticed was the one cap had to be hit harder than the other and also I couldn't get the clip in so I had to keep tapping that cap on little by little until I could gt the clip in and obviously with every tap it snugged up.
I'm probably just OCDing this but it was snug. Time will tell at this point. My understanding that if it is too tight it will wear out prematurely.
Click to expand...
The reason the joint feels tight after you have it all assembled is the "dog ears" that the caps press into get pressed closer together during the installation process. Once you have it completely assembled with all the clips in you need to spread the dog ears back out just enough to remove the bind.. You can (careful not to hit the u-joint itself) hit the dog ears on on the inside edge on each side of the joint until it frees up.
 
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mgroeger said:
I am able to take one hand and grab the exposed ends caps and swivel the joint without too much difficulty.
Click to expand...

If this is where you are, there is nothing else to do. The only part of the hammer action I could even think might help, but I probably still wouldn't do, would be tapping in the same direction as the driveshaft on each "ear" of the yoke, which would allow the cap to move if any pressure was being applied.

I'd also like to see the youtube video you watched.
 
JEEPCJTJ said:
If this is where you are, there is nothing else to do. The only part of the hammer action I could even think might help, but I probably still wouldn't do, would be tapping in the same direction as the driveshaft on each "ear" of the yoke, which would allow the cap to move if any pressure was being applied.

I'd also like to see the youtube video you watched.
Click to expand...


Here's the video. I understand what the other guy above is saying about tapping the "ears" out, I hadn't thought about that. However I think when you see the video where they are saying to tap the yoke you will see they are trying to achieve the same thing.
I think I will wait a week and pop the end of the shaft out of the diff yoke and see how it feels.
 
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They are always stiff. If it were loose then why change it. If the clips are in and properly seated then the joint is in correctly.👍 The non greaseable joints are normally even stiffer. Go ahead and put the driveshaft back in and run it.
 
mgroeger said:
Well it's VERY snug, is what it is at this point.......

What I noticed was the one cap had to be hit harder than the other and also I couldn't get the clip in so I had to keep tapping that cap......
Click to expand...

How snug is snug? You should still be able to grab it with your thumb and forefinger to move it full range without difficulty.

As pointed out in the video, you are sure that one of the needle bearings did not slip out of place when putting the cap on right? If you had to beat the heck out of just one cap and no others, there might have been a reason for that amount of force to be needed. It is easier to pop apart and check now than at a later date if it fails on the road....
 
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Hound Dog said:
How snug is snug? You should still be able to grab it with your thumb and forefinger to move it full range without difficulty.

As pointed out in the video, you are sure that one of the needle bearings did not slip out of place when putting the cap on right? If you had to beat the heck out of just one cap and no others, there might have been a reason for that amount of force to be needed. It is easier to pop apart and check now than at a later date if it fails on the road....
Click to expand...

I could grab with finger and thumb and move it, although it was stiff/snug.
I didn't have to beat the heck out of one of the caps, just was noting that one took a couple more wacks to get it in. I think the other poster was spot on that the dog ears on the yoke get slightly bent during the process of beating the caps out.
 
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DANG IT!
It's not singing anymore but still making a little chirp now and then. I suspect It's because it is too snug. Will remove tomorrow and try to loosen it up. Learn, learn, learn...
 
mgroeger said:
DANG IT!
It's not singing anymore but still making a little chirp now and then. I suspect It's because it is too snug. Will remove tomorrow and try to loosen it up. Learn, learn, learn...
Click to expand...
Is it one of the u-joint that's "chirping" or is it the center ball socket in the double cardan joint?
 
Not a bad video, pretty good actually. Whenever I've done this I used the vise as the press.

At 7:07, The "It may be necessary to strike the side of the yoke to relieve pressure on the u-joint..." is pretty much what I said I probably wouldn't do but now that I saw it I probably would. The split second "ringing" or vibration that striking creates loosens the yoke around the u-joint cap and lets whatever pressure is there to push it where it should have been to begin with. I'm sure this could be tried while still installed under the Jeep. You may want to try it before removing anything. It might save you some time.

At 7:18, They suggest the option "to strike the punch on top of both caps". That one I would avoid because I'd think it would just force the caps further in and cause more tightness. I might be the only one to think this way.
 
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JEEPCJTJ said:
Not a bad video, pretty good actually. Whenever I've done this I used the vise as the press.

At 7:07, The "It may be necessary to strike the side of the yoke to relieve pressure on the u-joint..." is pretty much what I said I probably wouldn't do but now that I saw it I probably would. The split second "ringing" or vibration that striking creates loosens the yoke around the u-joint cap and lets whatever pressure is there to push it where it should have been to begin with. I'm sure this could be tried while still installed under the Jeep. You may want to try it before removing anything. It might save you some time.

At 7:18, They suggest the option "to strike the punch on top of both caps". That one I would avoid because I'd think it would just force the caps further in and cause more tightness. I might be the only one to think this way.
Click to expand...

You're saying everything I'm thinking. However it literally takes less than 10 mins to remove the shaft so I will take it out tonight. I didn't think of pressing the caps in with the vice, that's a great idea. At the end of the day this cost me less than $20 on rock auto including shipping so I don't mind buying another and redoing if necessary. It's a good learning experience.
 
reddvltj said:
And you're sure it's not coming from the front shaft?
Click to expand...

Yep. I was under the Jeep (had it off the ground) when it was singing me a song and the noise was coming right from the U joint where it meets the diff area. After changing it the singing is gone and now a baby chirp happens once in awhile which tells me I'm on the right track.
Also when I took the old joint apart you could see the bearings had really scored the joint.
 
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If you pull it apart make sure that everything is super clean. A bit of rust can cause the cap to be off center and bind a tad. Good clean grooves too. Although I'm sure you made sure of that already.👍
 
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Goatman said:
If you pull it apart make sure that everything is super clean. A bit of rust can cause the cap to be off center and bind a tad. Good clean grooves too. Although I'm sure you made sure of that already.👍
Click to expand...

I did :)
My goal is to tap the dog ears outward since I'm sure they got slightly bent inward during the removal/install process. If I can't get the joint to move more freely I may go and take it all apart again. I have a spare joint that I can cobble any pieces that get damaged.
 
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