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Greaseable or Non-Greaseable U-Joints

  • Greaseable

    Votes: 3 75.0%
  • Non-Greaseable (sealed)

    Votes: 1 25.0%
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Discussion Starter · #1 ·
My new to me 06 Tahoe is making the tell-tale bad u-joint sound- clunking when putting it in to gear. It seems that most people recommend Spicer brand u-joints. But my question is do you prefer greaseable u-joints or the sealed ones and why?
I believe they came from the factory with sealed, non-greaseable joints, correct?
 

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I prefer guessable. But the "heavy duty" from companies like moog are not greaseable. Your clunk may not be a u joint. There are known issues with the slip yoke that slides into the trans. GM sells a zinc coated slope yoke to fix the issue. Mine does it about once a year. Just drop the drive shaft and grease the crap out of the yoke, inside and out. That will stop the clunk for about a year depending on weather conditions where you live
 

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Yes, I have the same joints in My truck. On one of the driveshafts. The other driveshaft has joints that have a zerk in the end of one of the caps. But they list an extreme duty that is not greaseable
 

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Honestly, don't know. I have seen nongreaseable Factory joints go 300,000+. I have had greaseable fail within 2 years of install. There are different theories on it, greaseable obviously lets you add grease, but some say that you run the chance of contaminating the joints with dirt every time you add grease. Some say non greaseable are the way to go. I prefer greaseable. Especially if it is a vehicle like my truck where I am putting a boat in the water with it. I can pump grease in the joint after and it pushes the water back out.
 

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I prefer guessable. But the "heavy duty" from companies like moog are not greaseable. Your clunk may not be a u joint. There are known issues with the slip yoke that slides into the trans. GM sells a zinc coated slope yoke to fix the issue. Mine does it about once a year. Just drop the drive shaft and grease the crap out of the yoke, inside and out. That will stop the clunk for about a year depending on weather conditions where you live
Hi Pikey - Can you give any more detail about this slip yoke? I have a 1999 2500 that does the clunk and a shudder in reverse. Chatted with Al (thegawd) about U joints, but mine seem pretty intact at the moment.
 

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The slip yoke is on the end of your driveshaft that slides into your trAns. It is a long (6-10") tube with splines on the inside. These splines slide over and mesh with the splines on your transmissions output shaft. If you pack a bunch of grease inside the hole thoroughly covering the splines And lube up the outside diameter and reinstall it then the clunk will go away. That is if you don't have a bad ujoint. I had a new tcase installed and they did not grease the slip yoke when they reinstalled it. It clunked when putting it in reverse and when putting it in drive. It would also clunk around corners while downshifting. I dropped the shaft and put atleast half a tub of grease in and on the yoke. The noise stopped. It is cheaper than buying the $200+ zinc coated yoke from GM. It takes about 10 minutes to do. While you have the shaft out you can also check the ujoints. If they are crunchy or stiff then I would replace them. It is worth trying for the cost of a tube of grease and 10 minutes of time. I don't bother jacking my truck up. I block the tires, crawl under it, break the ujoint strap bolts loose, crawl back out and put the truck in nuetral and then pry the shaft forward off the rear pinion yoke with a pry bar. I put it in nuetral because in park sometimes the shaft is under tension from the trans being in park and the vehicle weight rolled forward or backward in the park gear. It is hard to get the shaft out of the rear pinion yoke when this happens

As far as your shudder and clunk. The greased yoke might stop the clunk but I doubt it will effect the shudder. Do you know what trans is in it? I know that some of the GM truck transmissions are notorious for cracking the sunshell gear inside the trans. But when that happens you lose reverse all together. If you have a 4L60e trans give this test a try. Let us know the results. Here is a copy and paste of the test

Cause: two things make this transmission back up: one the reverse input clutches, can be wiped out due to bushing wear and ring damage on stator, second is low reverse clutches wiped out. you can determine which with simple test: drive forward and shift up to say 2nd or 3rd gear, not above 20mph max! take foot off accelerator and pull shifter into manual low, truck should pull into low gear and have engine braking, or feel like brake are on. If has low gear but just "coasts" away down the road then the low reverse clutches are the culprit. ( using downhill grade works best for this test.) If truck does have engine braking then your reverse problem is the reverse input clutches/drum.
 

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The slip yoke is on the end of your driveshaft that slides into your trAns. It is a long (6-10") tube with splines on the inside. These splines slide over and mesh with the splines on your transmissions output shaft. If you pack a bunch of grease inside the hole thoroughly covering the splines And lube up the outside diameter and reinstall it then the clunk will go away. That is if you don't have a bad ujoint. I had a new tcase installed and they did not grease the slip yoke when they reinstalled it. It clunked when putting it in reverse and when putting it in drive. It would also clunk around corners while downshifting. I dropped the shaft and put atleast half a tub of grease in and on the yoke. The noise stopped. It is cheaper than buying the $200+ zinc coated yoke from GM. It takes about 10 minutes to do. While you have the shaft out you can also check the ujoints. If they are crunchy or stiff then I would replace them. It is worth trying for the cost of a tube of grease and 10 minutes of time. I don't bother jacking my truck up. I block the tires, crawl under it, break the ujoint strap bolts loose, crawl back out and put the truck in nuetral and then pry the shaft forward off the rear pinion yoke with a pry bar. I put it in nuetral because in park sometimes the shaft is under tension from the trans being in park and the vehicle weight rolled forward or backward in the park gear. It is hard to get the shaft out of the rear pinion yoke when this happens
Thanks Pikey. So, this is on the back of the transmission. Are they pretty much the same between the years and between 4x4 and 2W drive trucks? Mine is of course a 4x4. In my case, it can't hurt to grease that part up - especially if it's never been done before. I just need to figure out the shuddering that also occurs in reverse.

I will look into this and update once I get around to it. Thanks again!
 

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Discussion Starter · #12 ·
There are known issues with the slip yoke that slides into the trans. GM sells a zinc coated slope yoke to fix the issue. Mine does it about once a year. Just drop the drive shaft and grease the crap out of the yoke, inside and out. That will stop the clunk for about a year depending on weather conditions where you live
thanks for the tip Pikey. Do you just use high-temp bearing grease or something else? Also what years are affected by this issue?
I'll drop the driveshaft and check that first and post update (it may be another 10 days or so, as we're expecting snow this weekend and it's tough for me to find time during the week). Glad I saw this before I ordered the new u-joints.
 

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The slip yoke is on the end of your driveshaft that slides into your trAns. It is a long (6-10") tube with splines on the inside. These splines slide over and mesh with the splines on your transmissions output shaft. If you pack a bunch of grease inside the hole thoroughly covering the splines And lube up the outside diameter and reinstall it then the clunk will go away. That is if you don't have a bad ujoint. I had a new tcase installed and they did not grease the slip yoke when they reinstalled it. It clunked when putting it in reverse and when putting it in drive. It would also clunk around corners while downshifting. I dropped the shaft and put atleast half a tub of grease in and on the yoke. The noise stopped. It is cheaper than buying the $200+ zinc coated yoke from GM. It takes about 10 minutes to do. While you have the shaft out you can also check the ujoints. If they are crunchy or stiff then I would replace them. It is worth trying for the cost of a tube of grease and 10 minutes of time. I don't bother jacking my truck up. I block the tires, crawl under it, break the ujoint strap bolts loose, crawl back out and put the truck in nuetral and then pry the shaft forward off the rear pinion yoke with a pry bar. I put it in nuetral because in park sometimes the shaft is under tension from the trans being in park and the vehicle weight rolled forward or backward in the park gear. It is hard to get the shaft out of the rear pinion yoke when this happens

As far as your shudder and clunk. The greased yoke might stop the

Pikey ,, my good lad! I need help and i think you may be the perfect person to help me with my dilemma.. i will try explaining to the best i can.
Around march my rear freeze plugs went out, so i had my moms "mechanic" drop my transmission and clutch plate, exhaust, ect... fixed my freeze plugs and reassemble. Since putting everything back together I have noticed quite a number of small issues, (gear selector displaced, exhaust leak) those are minor things i planned on fixing and didn't see a urgency in fixing those problems. As time goes by i started to hear a slight gear change clunk and checked i had enough ATF in the 460le which it looked fine. so i ignored it and figured that there was nothing i knew how to fix at that time.
A bit more time elapsed before i hear a rattle like my exhaust was falling out under the front seats when i put the truck in reverse.
Did not find the issue because its either been super hot or super cold outside lately. Anyways half way though my post something that i saw in one of your post proabaly just gave me the answer i was looking for. When pulling off my driveway my trucks left wheel was possessed by a daemon or something. Could the fact when i already had my right rear wheel fully on the curb and when i back up diagonally my wheel shot the wood that was helping me get up to my driveway flew out. Could my wheel wound up and then saved all of that power untill i drove back off the curb? because when i did my left rear wheel started chirping when i let off the gas the car was chirping like my differential was welded like a cheap drift car lol. please let me know if this is possible if that's not the problem or you are intrested in my other weird problems i can continue.

Sorry to thread jack.
 

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Wheels will not save power. What model and year is your truck? Is the rearend equipped with a g80 locker? When was the last time the fluid in the rear diff was changed?
 

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just got home from work, truck did semi good but i feel like the trans is slipping or yeah i guess the diff could be slipping. I have a 1999 gmc suburban with a 10 bolt rear diff and the last time it was changed was when i bought the truck in September by me. I can find the reference photo if you would like to know the weight or type of gear oil i used.
 
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