Greasable U-Joints ruin the yoke?

[Chris142]

Took the driveshaft out of my Truck to replace the center support bearing. I could not get it apart so I took it to the driveshaft guy.

He called me and said the yokes are all bad. The cups slide in with no resistance at all. He says that my greasing the Joints ruined the yokes.

He said that the grease gets between the cup and yoke which causes the cup to spin and wear the yoke.

Thoughts?

 

[wwillson]

He said that the grease gets between the cup and yoke which causes the cup to spin and wear the yoke.

That sounds like urban myth.

I've greased dozens of U-joints on machinery that not only are greasable, but if you don't grease them they won't last long. If you keep them greased they will last almost indefinitely.

 

[Chris142]

I agree that it sounds crazy. But my yokes are junk

 

[Gyro Gearloose]

I've never heard of any bearing design that depended on the rust to prevent the outer race from rotating.

 

[Number_35]

Took the driveshaft out of my Truck to replace the center support bearing. I could not get it apart so I took it to the driveshaft guy.

He called me and said the yokes are all bad. The cups slide in with no resistance at all. He says that my greasing the Joints ruined the yokes.

He said that the grease gets between the cup and yoke which causes the cup to spin and wear the yoke.

Thoughts?

Did the u-joints come from the factory with grease fittings?

I've heard that adding grease to sealed units such as tie rod ends can cause the components to fail prematurely, due to an incompatability between the factory grease and the new grease.

 

[Langanobob]

Have you seen the sloppy fit yourself? He’s mistaken if he thinks greasing u-joints will force grease around the outside of u-joint cups causing them to”spin.” If it were mine I’d take it somewhere else.

 

[Chris142]

Have you seen the sloppy fit yourself? He’s mistaken if he thinks greasing u-joints will force grease around the outside of u-joint cups causing them to”spin.” If it were mine I’d take it somewhere else.

Yes I went there after work. He said when they spin and sling grease it gets between the cup and yoke. After removing the clips all 3 joints can be pressed out with my fingers. I don't have another shop in an easy to go distance.

This guy has great reviews too. Either way my yokes are junk.

 

[Chris142]

Did the u-joints come from the factory with grease fittings?

I've heard that adding grease to sealed units such as tie rod ends can cause the components to fail prematurely, due to an incompatability between the factory grease and the new grease.

The originals were sealed. The replacements I put in 8 yrs ago have zerks.

 

[AutoMechanic]

Sounds like he is a real old timer. I’ve never heard such thing. I’ve done a few u-joints so by no means am I an expert on them but that sounds like one of those things they would of said back in the day because they don’t like a change in design.

 

[Chris142]

There is no doubt in my mind that my yokes are worn out. I saw it myself. But I am having a hard time believing that grease did it. The guy is much younger than I am.

 

[AutoMechanic]

I have doubts too that grease could of damaged them. That doesn’t seem right at all you would think grease would help them. Unless they were sealed and not meant to add grease which these were not sealed you mentioned so I don’t think it is grease.

 

[Lubener]

There is no doubt in my mind that my yokes are worn out. I saw it myself. But I am having a hard time believing that grease did it. The guy is much younger than I am.

Grease never wore out my yokes on my 87 and I have been greasing the joints twice a year since replacing the originals over two decades ago. I would believe a balance issue of the shaft, poor quality replacement joints or the carrier bearing wear causing a slight wobble of the shaft..

 

[RAR]

I doubt the grease had anything to do with that.. a more probable cause is if the joint wore to the point it began moving in the yoke ears, causing them to essentially wear and enlarge. I could envision this on an aluminum shaft. But - I’ve never seen a driveshaft yoke so worn out that you could press the joint in with your fingers.

I have two Ford aluminum driveshafts that are scrap because I used the method of pressing out the joint with my ball joint press. It worked on steel, so I did the same on the aluminum. Nope. Crushed the ears on the yoke enough to prevent the snap rings from seating properly. Lesson learned.. . I use the hammer method on them, and make sure I’ve only got one ear held so I’m not hammering them together.

 

[ka9mnx]

I wonder what your mechanics smoking?

 

[Astro14]

I doubt it’s the presence of a zerk that caused the problem...

However, a slightly under-sized cup, from a manufacturing defect or a poor manufacturing tolerance, could cause that cup to slam around in the yoke and enlarge the yoke to the point that it needs to be replaced.

 

[Chris142]

I wonder what your mechanics smoking?

Local driveline shop.

 

[Chris142]

I doubt it’s the presence of a zerk that caused the problem...

However, a slightly under-sized cup, from a manufacturing defect or a poor manufacturing tolerance, could cause that cup to slam around in the yoke and enlarge the yoke to the point that it needs to be replaced.

Sounds more plausable to me.

 

[Trav]

I doubt it’s the presence of a zerk that caused the problem...

However, a slightly under-sized cup, from a manufacturing defect or a poor manufacturing tolerance, could cause that cup to slam around in the yoke and enlarge the yoke to the point that it needs to be replaced.

That sounds more like it. I would clean and measure the yoke and buy joints by size and cup size. A couple of examples, it wouldn't surprise me if the ones you got were slightly undersized. Greasing the joints did not cause this, find another shop or do it yourself, a machine shop can size oversized cups for you.

https://www.transamericanwholesale....int.aspx?t_c=12&t_s=515&t_pt=3624&t_pl=102547

https://media.spicerparts.com/cfs/files/media/9Mn5KaTiB5f9a6vgJ/J3348-92015.pdf?store=original

 

[SwampSurvivor]

I have two Ford aluminum driveshafts that are scrap because I used the method of pressing out the joint with my ball joint press. It worked on steel, so I did the same on the aluminum. Nope. Crushed the ears on the yoke enough to prevent the snap rings from seating properly. Lesson learned.. . I use the hammer method on them, and make sure I’ve only got one ear held so I’m not hammering them together.

I've messed up a few yokes with a press. As much as I hate doing it, I just hammer them in/ out now.

 

[Trav]

I just use my big vise with a couple of sockets. It is incredible the amount of finesse you can get with a vise. If you tweak the ears just make something like this to straighten them.