First link is a good price!
The second link was the one in going to buy lol he’s about 20 min from me
Transfer case exploded
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First link is a good price!
The second link was the one in going to buy lol he’s about 20 min from me
Do not know what he is, shop ?? If so may get him to put 23 sp input and your SYE in ?? Internals different ??
21 sp input shaft, was for 4 cyn TJ. Can be exchanged for a 23 but wonder if that is all the difference in the TC's ?? Smaller chain etc ?? Don't know.
Might call Advance Adapt or Novak if questions. D
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Not sure what he is. I can just see the link. I don’t have Facebook.
I’m wondering what he means by 21 spline?
The rear spline where the stock driveshaft slips onto. If so I will be removing that output shaft.
21 spline is referring to the input of the transfer case, where it slips onto the transmission. You would need a 23 spline. Best plan would be to take the input gear out of your old transfer case and install it into the new one if the new one doesn't come with a 23 spline. Input gear from the blown transfer case is likely fine. Although that would need to be confirmed upon disassembly.
Hey all, I want to weigh in on the greaseable vs non-greaseable socket yoke thing. I've only skimmed the forum conversation so forgive me if anything I say is out of context.
Here's the thing with non-greaseable parts. Does non-greaseable mean the parts don't need grease or just that you can't grease them? I lean towards the latter. In the image below, I have a couple photos comparing the cross section of a greaseable and non-greaseable socket yoke. There are two important parts to observe. One is the seat that the ball rides against. The seat is on the bottom half of the centering ball, there are grooves that serve as grease channels to bring grease up from the pocket below the ball to the contact area of the seat. The other thing to look at is the grease pocket itself. This is the same size on both socket yokes. There's a very small reservoir for grease. The only key difference between the two is that the non-geaseable socket yoke doesn't have a grease fitting and it has a boot (on the weld yoke) that covers the top of the socket yoke and the top of the ball. But because the top of the ball is not the part that makes contact with the seat this doesn't do much to keep grease in the bottom of the ball. It does protect the socket yoke from dirt and water but not entirely. The other thing not pictured that you'll have to imagine for this to make sense is that there is a pin that goes in the ball, where the needle bearings go. This pin acts as a plug, so grease doesn't evacuate up through the center of the ball. That also means that you could pack the rubber boot full of grease but the grease won't find its way down to the bottom of the ball.
But what about the stock shaft with the non-greasable socket yoke that lasts 100K miles? This is a fairly common occurrence. But how many of those miles were with a suspension lift? At stock angles things last a long time. At stock angles, stock drive shafts work well. It is when a lift is installed and the angles are significantly increased that the life expectancy diminishes. This is for two reasons, one is that the ball pivots more, you're working the ball at more angle which produces more friction and causes it to wear out more quickly. The other is the boot itself is more likely to fail on a lifted jeep. If I handed you a piece of rubber and told you I'd give you $100 if you could tear it in half with your bare hands you'd immediately start bending it back and forth a bunch to fatigue and weaken the rubber. This same sort of thing happens when the drive shaft is spinning at significant angles. Then the rubber cracks or splits and the boot looses its ability to protect the socket yoke. That and sometimes the boot will get pried off the weld yoke entirely.
Those are the reasons we always use greaseable socket yokes when possible. Because we are dealing with almost 100% lifted vehicles. In our experience the greaseable socket yokes work better at the angles found in lifted Jeeps. However, the need to grease the socket yoke is often overlooked so many people still have failures of their greaseable centering ball. There is no perfect design when it comes to this part of the shaft.
For 1350 series shafts, we get the best of both worlds. Neapco makes weld yokes that have a grease fitting under the pin of the weld yoke, the grease gets pumped in under the pin and travels up/down the pin and is injected into the cavity under the ball. With this design you are able to run the rubber boot but still have the ability to put new grease into the socket yoke. That's my favorite setup, but unfortunately these greaseable weld yokes don't exist for 1310 series shafts and 1350 series is generally too big for a TJ.
Here's the thing with non-greaseable parts. Does non-greaseable mean the parts don't need grease or just that you can't grease them? I lean towards the latter. In the image below, I have a couple photos comparing the cross section of a greaseable and non-greaseable socket yoke. There are two important parts to observe. One is the seat that the ball rides against. The seat is on the bottom half of the centering ball, there are grooves that serve as grease channels to bring grease up from the pocket below the ball to the contact area of the seat. The other thing to look at is the grease pocket itself. This is the same size on both socket yokes. There's a very small reservoir for grease. The only key difference between the two is that the non-geaseable socket yoke doesn't have a grease fitting and it has a boot (on the weld yoke) that covers the top of the socket yoke and the top of the ball. But because the top of the ball is not the part that makes contact with the seat this doesn't do much to keep grease in the bottom of the ball. It does protect the socket yoke from dirt and water but not entirely. The other thing not pictured that you'll have to imagine for this to make sense is that there is a pin that goes in the ball, where the needle bearings go. This pin acts as a plug, so grease doesn't evacuate up through the center of the ball. That also means that you could pack the rubber boot full of grease but the grease won't find its way down to the bottom of the ball.
But what about the stock shaft with the non-greasable socket yoke that lasts 100K miles? This is a fairly common occurrence. But how many of those miles were with a suspension lift? At stock angles things last a long time. At stock angles, stock drive shafts work well. It is when a lift is installed and the angles are significantly increased that the life expectancy diminishes. This is for two reasons, one is that the ball pivots more, you're working the ball at more angle which produces more friction and causes it to wear out more quickly. The other is the boot itself is more likely to fail on a lifted jeep. If I handed you a piece of rubber and told you I'd give you $100 if you could tear it in half with your bare hands you'd immediately start bending it back and forth a bunch to fatigue and weaken the rubber. This same sort of thing happens when the drive shaft is spinning at significant angles. Then the rubber cracks or splits and the boot looses its ability to protect the socket yoke. That and sometimes the boot will get pried off the weld yoke entirely.
Those are the reasons we always use greaseable socket yokes when possible. Because we are dealing with almost 100% lifted vehicles. In our experience the greaseable socket yokes work better at the angles found in lifted Jeeps. However, the need to grease the socket yoke is often overlooked so many people still have failures of their greaseable centering ball. There is no perfect design when it comes to this part of the shaft.
For 1350 series shafts, we get the best of both worlds. Neapco makes weld yokes that have a grease fitting under the pin of the weld yoke, the grease gets pumped in under the pin and travels up/down the pin and is injected into the cavity under the ball. With this design you are able to run the rubber boot but still have the ability to put new grease into the socket yoke. That's my favorite setup, but unfortunately these greaseable weld yokes don't exist for 1310 series shafts and 1350 series is generally too big for a TJ.
By the way, I cut the non-greaseable socket yoke in half, and took and edited the photos today, just for this post
The centering ball of a double cardan is exactly the same size and basically the same design in 1310, 1330 (TJ Rubicon), 1350, and even 1410 series drive shafts. The vulnerability of the center ball and its likelihood to fail is essentially the same is any drive shaft. The only two things that significantly affect the life of the center ball are grease and angle.
The centering ball of a double cardan is exactly the same size and basically the same design in 1310, 1330 (TJ Rubicon), 1350, and even 1410 series drive shafts. The vulnerability of the center ball and its likelihood to fail is essentially the same is any drive shaft. The only two things that significantly affect the life of the center ball are grease and angle.
Certainly a fair point that I was not thinking as much about when I was referring to the reliability of the stock front shaft and how they all were non-greasable. That could also explain why many of them fail on the forum, because they are often still stock and probably subjected to new larger angles as the vast majority of forum users have some amount of lift. I'm sure with enough miles and years even at stock height they wear out, but the lift on any TJ likely exacerbates and shortens the life.
It's really too bad that greasing the greasable one is as much of a pain as it is. Making that easier to do would be the ideal solution with people subjecting their driveshafts to taller than stock lift heights that wear them out more quickly.
I know I just looked at my front adams unit,gonna have to remove the UCF skid ,and maybe the shaft itself.
Even after buying a longer needle I still had to remove the rear to get any grease in?
you're a legend. thanks for the visual aids sir!
that's really my problem. I don't mind the rear as much, but for the front it's either support the transmission and drop my 80lb skid plate, or set up a fiddly magnetic work light and get the needle into the zerk looking between the frame and tub, where I can either see whether grease is spilling out of the needle that isn't lined up well enough, or coming out of the ball, but not both. Pulling the shaft is an equal PITA because my skid is aftermarket and doesn't have the handy little window to stick a wrench through to loosen the bolts, and because they have a 7/16" head instead of the original 5/16", which is too big for a ratcheting wrench to fit around so it's a combo wrench 1/4 turn at a time. Then reinstalling the shaft sucks because I have a HP axle and the shaft needs to compress when the axle droops, so I had the shaft built just a hair short, which means the boot is stretched a bit from it's natural position and I have to pull tension on it to get bolts started.
The amount of work involved means I end up greasing when I'm about to leave on a road trip and realize I don't remember the last time I did it, and i do a half ass job at it and end up spinning grease all over the bottom of the tub once I drive because I'm shooting blind without dropping the skid.
that's why you're one of our favorite vendor-members!
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