Premature u-joint wear

For what its worth ......I was having a similar problem on rear drive shaft u-joints wearing out about once a year. I consulted someone who is a "wizard" of sorts on TJ' s and he recommended switching to a "high speed" grease. I started using Lucas 10301 in the green tube. Problem gone!

Interesting, may have to get some greasable u-joints and go that route. I’ve been using non-greasable Dana ones.
 
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Interesting, may have to get some greasable u-joints and go that route. I’ve been using non-greasable Dana ones.
In the driveshaft greasable u-joints are not as strong nor as durable, especially when compared to the sealed Spicer 5-1310x which is very hard to beat in a TJ. Greasable driveshaft u-joints like the Spicer 5-153x have a grease zerk in the body and the grease journals drilled inside it weaken the u-joint body. Generally speaking it's only a good idea to run greasable u-joints if you're doing a lot of mud pits/deep soupy mud.
 
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In the driveshaft greasable u-joints are not as strong nor as durable, especially when compared to the sealed Spicer 5-1310x which is very hard to beat in a TJ. Greasable driveshaft u-joints like the Spicer 5-153x have a grease zerk in the body and the grease journals drilled inside it weaken the u-joint body. Generally speaking it's only a good idea to run greasable u-joints if you're doing a lot of mud pits/deep soupy mud.

Agreed and if he was breaking u-joints that would be a major factor. His joints seem to be lasting about a year and then failing due to premature wear, indicating to me lack of lubrication. If the grease fitting in the body of a 153x is concerning just get the 5-1310-1x. It is the exact same u-joint as the 5-1310 with the addition of a grease fitting in one of the caps giving you the ability the service it with fresh grease and no compromise in strength. looks like @Flexlex is in Georgia so I imagine he is no stranger mud.
 
Some more info:

Drive shaft angle is 16.6 which works out to working angles of 10.6 at the T-case and 5.8 at the pinion.

Control arms as is are stock length
 
Some more info:

Drive shaft angle is 16.6 which works out to working angles of 10.6 at the T-case and 5.8 at the pinion.

Control arms as is are stock length
The driveshaft angle itself is irrelevant, only the pinion shaft and t-case angles are important and they need to be very close to the same... parallel to each other.
 
The driveshaft angle itself is irrelevant, only the pinion shaft and t-case angles are important and they need to be very close to the same... parallel to each other.

If you had parallel t-case and pinion at 0 degrees but say a 45 degree slope on the shaft, you would probably break stuff pretty quick. According to one of the vids on Tom Woods custom driveshaft you-tube, working angles under 10 degrees are ideal. To get those numbers you subtract the angle at the TC from the drive shaft, repeat for the pinion.

Opinions probably vary but the working angles should be parallel and under 10-15 degrees? I’m open to what folks think is ok. If I adjust the pinion down I will get working angles over 10 degrees but my math isn’t good enough to calculate what they would be given the desired angle. May have to learn some trig!
 
If you had parallel t-case and pinion at 0 degrees but say a 45 degree slope on the shaft, you would probably break stuff pretty quick. According to one of the vids on Tom Woods custom driveshaft you-tube, working angles under 10 degrees are ideal. To get those numbers you subtract the angle at the TC from the drive shaft, repeat for the pinion.

Opinions probably vary but the working angles should be parallel and under 10-15 degrees? I’m open to what folks think is ok. If I adjust the pinion down I will get working angles over 10 degrees but my math isn’t good enough to calculate what they would be given the desired angle. May have to learn some trig!
I guess I just don't know nuthin' about the subject then. You're having trouble with premature u-joint wear with only a 1.5" suspension lift and it's clear you believe you know the answers so it should be easy for you to stop the premature wear.
 
That would lead me to looking closely at the pinion yoke and make sure it is not worn excessively.

Here’s a pick of the yoke:
There is some play left to right with the Ujoint in the yoke.

02FABA04-FE0A-4A8C-8383-103E0334EE5F.jpeg
 
Here’s a pick of the yoke:
There is some play left to right with the Ujoint in the yoke.

View attachment 476801

What kind of play are you talking about, a couple thousands of an inch? Because it really shouldn’t move side to side at all!

And I find the way that the seats are cut in your yoke look weird. They’re not fully cut in the casting. It’s been a while since I’ve looked at mine, or any other yoke, but I recall the yoke having a full radius cut for the bearing cups.

IDK, maybe that yoke doesn’t hold the bearing cups correctly, allowing the joint to move around and cause excessive wear!
 
What kind of play are you talking about, a couple thousands of an inch? Because it really shouldn’t move side to side at all!

And I find the way that the seats are cut in your yoke look weird. They’re not fully cut in the casting. It’s been a while since I’ve looked at mine, or any other yoke, but I recall the yoke having a full radius cut for the bearing cups.

IDK, maybe that yoke doesn’t hold the bearing cups correctly, allowing the joint to move around and cause excessive wear!

1700936048664.png

Here’s a new one but yea, just barely some side to side play without the Ujoint strapped in.
 
I guess I just don't know nuthin' about the subject then. You're having trouble with premature u-joint wear with only a 1.5" suspension lift and it's clear you believe you know the answers so it should be easy for you to stop the premature wear.

Jerry, the OP is not saying that "you don't know nuthin", he's gently presenting his information, and he's right. Take it easy.

The driveshaft angle is relevant for calculating the angles of each U-joint, and that's how the OP is using it, so saying it's irrelevant isn't helping.

Drive shaft angle is 16.6 which works out to working angles of 10.6 at the T-case and 5.8 at the pinion.

I wouldn't rotate the pinion down, that will increase the angles at both ends, which won't be good for the U-joints. I tried that, and while I was able to match the pinion and tailshaft angles fairly well, both U-joints were working at over 10° and I had vibes.

Instead, I would either lower the skid plate, or better, add a motor mount lift (MML). That will lower the tailshaft, reducing the angle of both U-joints, especially the front one. Lowering the skid with washers is a cheap way to find out if changing that angle will fix your problem. Either way, though, you may have to mess with your shifter if it bumps into the rear of the tunnel hole or the boot bezel.
 
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The driveshaft angle is relevant for calculating the angles of each U-joint, and that's how the OP is using it, so saying it's irrelevant isn't helping.
With only a 1.5" suspension lift the angle of the driveshaft is irrelevant. What's important is the pinion shaft and t-case shaft angles need to be parallel with his factory single-cardan driveshaft. In his case those angles are not parallel as they must be.
 
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Jerry, the OP is not saying that "you don't know nuthin", he's gently presenting his information, and he's right. Take it easy.

The driveshaft angle is relevant for calculating the angles of each U-joint, and that's how the OP is using it, so saying it's irrelevant isn't helping.



I wouldn't rotate the pinion down, that will increase the angles at both ends, which won't be good for the U-joints. I tried that, and while I was able to match the pinion and tailshaft angles fairly well, both U-joints were working at over 10° and I had vibes.

Instead, I would either lower the skid plate, or better, add a motor mount lift (MML). That will lower the tailshaft, reducing the angle of both U-joints, especially the front one. Lowering the skid with washers is a cheap way to find out if changing that angle will fix your problem. Either way, though, you may have to mess with your shifter if it bumps into the rear of the tunnel hole or the boot bezel.
Thanks, this makes sense and is probably the way to go if I stick with the stock driveshaft.
 
You really need to figure out why your tcase output shaft and pinion shaft angles are so different, they (again) need to be parallel. After that repeated suggestion/point I'm giving up.