Drive shaft popped out while swapping leafs. Now pinging and tinging

Hello!

I was installing my new OME leafs today when the pumpkin slipped off the jack and fell onto the jack's piston. It didn't hit the ground, but the angle change was enough for the drive shaft to separate near the rear differential. I finished installing the new rear suspension and removed the bit of drive shaft still bolted to the diff. I joined the two bits of drive shaft together again, being mindful of their orientation and a weight on the u-joint, and bolted it back onto the diff.

After torquing everything to spec, we put the wheels back on and went for a spin. Not even thirty seconds later we started hearing a pinging, similar to what you'd hear with tranny issues but coming from the back. It was definitely related to speed too. It's not a constant noise or predictable one, but intermittent enough that I'm worried to drive it anywhere.

How boned am I? Any idea of what I might have done or can do to fix it? Tempted to pull the drive shaft off the diff again, but I don't understand what's pinging. I'm fairly sure I got the grooves between the parts aligned, but I really can't be certain because I didn't mark it before it fell apart. @BartMaster1234 @jbrandt Any ideas?

 

So all that happened is the driveshaft came off it’s slip yoke?

If could be the balance is off on the driveshaft, but it could be also something else. Hard to tell.

 

Yeah, just popped off. Could the balance cause the metallic tinging? It's hard to narrow down because it has to be in drive, but it's definitely coming from between the carrier bearing and the diff.

Just not sure if I should be driving it or not, or whether this is shop worthy.

 

Sounds to be like a driveline balance issue. But it could also be something else.

If you can record the sound that would
Help.

 

It's not a constant ping or following any pattern. I couldn't get one of the bolts torqued as much as I'd like. Would an under-torqued bolt on the slip yoke cause that?

I'll see if I can get a recording of the sound real quick. Hold please.

 

Ah, couldn’t upload it directly. Does this link work for you?
https://1drv.ms/v/s!Ai8zvSIVGTzzhPwrYyFsKiETI3HKGg

Also more severe vibrations than I'm used to at 10 mph and slower. Not too bad in the 20s though

 

Well, I torqued those nuts down again and it's still pinging. I needed to have my u joints replaced anyway. I'll take it into the shop tomorrow with the u joints and ask them to diagnose it. I'll keep the thread updated.

At least my new suspension is on!

 

U-joints can defiantly cause it. You've changed the angle of the u-joints by lifting it. Have you tried greasing them?

 

You might try putting the rear end up on jack stands, turn the wheels by hand, and see if you can narrow down where the sound is coming from.

 

did you make sure the u-joints were still in phase?

 

Make sure u joins are lined up the same from diff and center carrier bearing. The “fork/ujoint” need to be aligned the same

 

Like this

 

Thank you for all of your replies! The shop I called wanted like $700 to do the u-joints and diagnose/fix the issue. So that's definitely off the table.

The U-joints were in rough shape before the lift, squeaking and creaking pretty badly in forward in reverse. So much so that I bought new u-joints a while back and was planning to do them at some point. I guess that point is now. I wonder if the pinging is them binding at the new angles? I feel confident I put the slip yoke on aligned how it was before they separated. The truck was in park and the slip yoke would only bolt up when attached at one angle. I also read that some people recommend ordering a carrier bearing drop kit or putting in about 6" of washers to remove that distance and get rid of the vibrations I'm feeling.

I think I'll remove the drive shaft tonight and take a stab at replacing the u-joints. Hopefully that resolves the pinging and the vibration. If the vibration is still there I'll get some washers and drop the carrier bearing.

I've never greased these before, it looks like they have grease nipples. What would you buy to pump grease in those? Also, would you use the same moly grease that the shackles use?

EDIT:
Any advice or guides on how to do the u-joints would be greatly appreciated. I only have tonight to finish up work on the truck. So far I've found Timmy the toolman's youtube guide, but I want to become an expert on it before trying it.

 

Is there a particular way of aligning them other than bolting them up? Feeling pretty confident that the weights are balanced, but there's no way of knowing until I get those pesky u-joints replaced.

Thanks! I'll give this a shot tonight. I thought about putting the rear on jack stands and slowly accelerating, but I had visions of ferris bueller's day off and decided that was an awful idea

 

When you take apart the slip yoke you have to be mindful to mark it so you can put it back together the exact same way/position that it came out, sounds like maybe it wasn't put back in exactly the same way.

I've had that metal "PING" coming from my slip yoke for awhile now when I go from forward to reverse or let off the accelerator, which is an indication that the slip yoke needs greasing (by hand since the zerk doesn't get the grease up to the splines). Maybe you need to grease it but I'm betting it wasn't put back in the same position as it came out

 

It's a good idea to grease the zerk fittings on the driveshaft every oil change or so, but the zerk fitting for the slip yoke doesn't do a good job of getting the grease up to the splines of the slip yoke and if you over grease that fitting, it can prevent the slip yoke from moving the way it was designed to. Best way to do it is to remove it (the right way, not by letting it fall off a jack stand haha) and grease the splines by hand

 

Hah, yeah. Really wish I would have marked them ahead of time. As far as greasing all of this, should I continue using moly based lubes? I believe this is what I used for the leaf shackes.

 

Yeah that should work, I've heard the stuff by Motorcraft called XG-8 (if I remember right) is the best kind to use, but it's pricey

 

These two videos will help.

 

Man, I owe Timmy a lot of beers. Thank you for shooting these over!