M816 Crane Drive CV Joints

[Flyboy207]

Hello all,

I’m working on my XM816’s crane driveshaft. The truck came to me missing the short side of the shaft (lower/front). I got the upper shaft, CV, and boot off yesterday to facilitate breaking the boot bearing loose, and I got the CV out of the power divider PTO housing.

To confirm, this is the part that fails, correct? Not the actual
bearings in the oval shaped housing?


So far, mine don’t look terrible, but I haven’t really gotten into them yet. One thing that really confuses me: I’m told (and confirmed by the Lubrication Order) that filling the oval shaped housing up to the plug level will put gear oil into the boot and lubricate the CV. Now, every CV I’ve dealt with on a pickup or car uses grease, not oil as a lubricant. Admittedly the system is a bit different, but is there a way to grease these CV’s to extend their life?

I’m really not looking forward to blowing these up and having to custom machine a solution, so I’d like them to survive as long as can reasonably be expected.

Thanks!

 

[Flyboy207]

Continuing to work on this project… I disassembled both of the CV joints to check on their condition. One had damaged balls, and both show a considerable amount of galling between the cage and the race. I’m hoping I can get these cleaned up enough to run just briefly, then look into changing the shaft out later.

 

[WillWagner]

Yeah, I wouldn't run those at all. IF you get something up in the air and swung to one side or the other, unless you have another vehicle there to push the boom over, you are stuck.

I would find a local truck drive shaft shop and see if they can locate the bearings or build you a new shaft. Seems that a more modern CV grease would do better than gear oil.

 

[Flyboy207]

Yeah, I wouldn't run those at all. IF you get something up in the air and swung to one side or the other, unless you have another vehicle there to push the boom over, you are stuck.

I would find a local truck drive shaft shop and see if they can locate the bearings or build you a new shaft. Seems that a more modern CV grease would do better than gear oil.

I cleaned them up and put them back together, they’re a little chunky but they should work at least long enough to spool the cable drum out a little. Remember, all I’m trying to do is turn the drum so I can plug the holes and deal with the bees. The drum is a worm drive, so it’s the ONE thing on the crane that I can’t move with a forklift.

A buddy of mine helped me with the CV’s and looked at the drive setup, he’s used to lineman and digger derrick trucks… he had some interesting things to say about the setup on the wreckers. I guess I’m going to find out if this works, or if it’s just going to explode… which doesn’t really change my predicament even if it does!