Driveshaft woes

[Peakbagger]

A few days ago, I was in a hurry to get to an appointment and decided to jump on 470. Speed limit on this highway is 75 and I was pushing it to around 80, which is not unusual. After the appointment, as I was driving home, I started hearing a new noise coming from the center console/shifter area. It sounded like a fan motor or a bearing giving out. The noise would start up as I passed 30 mph and stay consistent, perhaps a bit of change based on RPM, until I dropped below 15 mph and then the noise would disappear. I have heard the advice given here for years and the first thing I did was check all of the fluids. Everything checked out. Next, I dropped the skid plate and removed the front driveshaft. Replaced the skid plate and went for a drive. No more noise could be heard. Examining the driveshaft itself and moving the double cardan around, it feels like it is catching about every 1/4 turn. I am guessing it should feel smooth throughout the range of motion. I have already ordered a new driveshaft, but I have some questions. First, the old driveshaft is not that old. I replaced it when I replaced the transfer case with an Atlas. Since then, my health failed and I have not been on many trails and none I would consider extreme. There are less than 2500 miles on the Jeep since the change.

What would cause the driveshaft to fail so quickly, and without any hard wheeling? Is there something I might have done wrong to cause the failure? Is there anything I should do in the future to prevent this? I have ordered a non greasable driveshaft as before. I always greased the one zirc on the shaft which is near the splines. Have a I missed something?

2000 TJ, 4.0, 32rh, Atlas 5:1 2 speed, Tom Woods shafts

Thanks for looking.

Scott

 

[lBasket]

I'd probably be calling Tom Woods and seeing what they think, honestly

 

[Peakbagger]

I plan to, but thought there might be some expertise here in the meantime.

 

[macleanflood]

It's probably the u-joints, not the shaft itself.

Greaseable or not?

-Mac

 

[Peakbagger]

Joints are non greasable. There is one zirc on the shaft, between the front u joint and the splines. I have kept this one greased with Lucas red and Tacky.

 

[JKP]

Unless you specified a sealed centering ball yoke, there is a flat zerk for it, and that's probably what has dried out.

 

[macleanflood]

Needle zerk technically speaking...

-Mac

 

[Peakbagger]

I just looked at my driveshaft and there was a dark spot in that location. I cleaned it off a bit and found a hole where that silver piece probably lived at one time. If it was there when I received the shaft it certainly is not there now. Thanks, you may have solved the mystery.

 

[JKP]

Also, if you don't want to have to drop the driveshaft every 6 months or so to grease that, call TW and tell them you want the sealed centering ball yoke. They are big believers in the greaseable centering ball, but my stock Rubi shaft went 250K with a sealed one.

My TW shaft is sealed everywhere but the centering ball as I forgot to spec the sealed one. Sealed U joints, sealed slip, but greaseable centering ball.

 

[JKP]

I just looked at my driveshaft and there was a dark spot in that location. I cleaned it off a bit and found a hole where that silver piece probably lived at one time. If it was there when I received the shaft it certainly is not there now. Thanks, you may have solved the mystery.

Yep, without the zerk it threw the grease out and let water in.

 

[MountaineerTom]

Tom Woods sends a plastic fitting to grease that centering ball but I found it to be too big to fit in there. Maybe if it were off the Jeep you’d have room to maneuver it and get in there, I don’t know.

I got one of these Lock-N Lube needle needle dispensers and was able to get it in there with the driveshaft installed on the Jeep to grease it. You may need to roll the Jeep forward or back a little to get the correct access angle though.

Looks like you’ll still need the greas fitting though. I’m sure Tom Woods would send one out.

https://www.amazon.com/dp/B0779FK9CZ?tag=wranglerorg-20