Nashville TJ's Build - Continued

[Wildman]

Yeah, I just ordered the thing. 1600 clams to my door. Definitely the easiest solution - but those are generally also the most expensive.

But, I did sell my six China Bombs for $650 this morning, so I'm not too far behind on the day...

Well when I'm ready to go to a 14 bolt if you want to sell the old one... Knowing I'd need to replace that half of the case.

 

[NashvilleTJ]

Well when I'm ready to go to a 14 bolt if you want to sell the old one... Knowing I'd need to replace that half of the case.

If you want it, it's yours.

 

[Wildman]

If you want it, it's yours.

Bring it to Sand Hollow if you have the room.

 

[mrblaine]

I pulled the carrier this afternoon - and I'm at a bit of a loss. The ring and pinion looks fine. The carrier bearings look fine. The pinion bearings feel fine. The spindle bearing on each side feel fine. There was no debris on the gear oil.

View attachment 666202

But there is this: When I rebuilt this thing this time last year I had an issue with the passenger side case bearing being loose. ARB told me this was not an uncommon problem, and the fix was to dimple the bearing surface and press it on. Well, it's loose again and once again came off in my hand.

View attachment 666203

The scoring may have been there from the last occurrence, but the dimples are clearly worn off.

View attachment 666204

I checked the runout on both axle shafts. The passenger side was 21 thou. Not great, but I don't think horrible enough to cause any issues. The driver side was 13 thou. I'll pull out my spare stock shafts and compare the runout.

View attachment 666205

Backlash on the R&P was 22. Again, not great, but I don't know what the tolerance is for a broken-in 14-bolt gear set. It was certainly in spec when I built it.

So I did not see the smoking gun I expected. I'll have to address the loose bearing surface, and that may require a new locker this time. I considered that last year, but decided to see how well the dimple method worked. It did work initially, but obviously was not a permanent fix. And again, I have no idea if that had anything to do with the noise.

So help a brother out: Any ideas?

The purpose of the dimples is to add thickness. Yours are way too deep and not nearly enough. You need to use a sharp center punch, moderate tap, and then do that in a 1/8" x 1/8" pattern on the journal. Press the bearing on with some 609 or 638 and it will last a very long time.

Your better indicator of shafts being true is to measure the face of the flange and whether that is running true to the spline concentricity. What it does between those two points is inconsequential.

 

[srimes]

Problem is that the bearing - as it did before - moves a bit on the bearing surface. I just went out and measured it, and the bearing collar moves back and forth 14 thou on the bearing retainer. That means there is no way to keep the bearing concentric with the bearing surface, and the 609 would not help that - even if it held.

The first time I did this I did my best to make the dimples consistent, hoping to get the bearing close to concentric - but of course that's never going to be spot on. Maybe that lack of concentricity contributed to the failure? No idea, but it would only be worse if I tried the dimple approach again.

Of course, I still have no idea what led to spinning the bearing the first time.

I read @horsejockey61 's comment as using the loctite on the new carrier to help keep it from happening again.

Some people that push diffs hard will go spool. Sure is nice being able to unlock, though.

 

[NashvilleTJ]

I read @horsejockey61 's comment as using the loctite on the new carrier to help keep it from happening again.

...

Gotcha. I missed that, sorry Mike. That makes sense - especially since I don't know what caused the problem to start with. I'll do that when I install the new bearings on the new carrier.

 

[NashvilleTJ]

The purpose of the dimples is to add thickness. Yours are way too deep and not nearly enough. You need to use a sharp center punch, moderate tap, and then do that in a 1/8" x 1/8" pattern on the journal. Press the bearing on with some 609 or 638 and it will last a very long time.

Your better indicator of shafts being true is to measure the face of the flange and whether that is running true to the spline concentricity. What it does between those two points is inconsequential.

Thanks Blaine. I do understand the thickness part, it was my technique which was flawed. You did point that out when I did it the first time. But since I did it incorrectly, and added all those big holes, I don't think I can correct it at this point, so a new locker it is.

Do you think the idea of using 609 to the new assembly has any merit?

 

[hosejockey61]

I read @horsejockey61 's comment as using the loctite on the new carrier to help keep it from happening again.

Some people that push diffs hard will go spool. Sure is nice being able to unlock, though.

Negative. With existing locker.

 

[hosejockey61]

I was

Gotcha. I missed that, sorry Mike. That makes sense - especially since I don't know what caused the problem to start with. I'll do that when I install the new bearings on the new carrier.

I was referring to the current situation.

 

[NashvilleTJ]

Bring it to Sand Hollow if you have the room.

Done. One thing - it will be packaged in a brand spanking new ARB box!

By the way, it's the ARB RD114, which is the 30 spline, 4.10 and down carrier.

 

[mrblaine]

Do you think the idea of using 609 to the new assembly has any merit?

609 retains the bearing or sleeve. They aren't moving due to anything the 609 would fix since the preload on the bearing is doing the retaining. But, if the housing was flexing, that would load the bearing on one side as it rotated and eventually cause a loss in interference which again, the Loctite won't prevent. You need to stop whatever is causing the bearing to be loaded unevenly or just resign yourself to keeping a ready to go locker on the shelf to mitigate downtime.

 

[NashvilleTJ]

I was


I was referring to the current situation.

Gotcha, then I did understand what you were saying. But, I do like the idea of potentially using it on the new setup. Just not sure if it would make a difference when using it with a tight press fit.

 

[Wildman]

Done. One thing - it will be packaged in a brand spanking new ARB box!

By the way, it's the ARB RD114, which is the 30 spline, 4.10 and down carrier.

That is fine... Will work with what I had planned too.

Thanks Jeff. And I'll try Blaines tip on that case too and see what happens.

 

[NashvilleTJ]

609 retains the bearing or sleeve. They aren't moving due to anything the 609 would fix since the preload on the bearing is doing the retaining. But, if the housing was flexing, that would load the bearing on one side as it rotated and eventually cause a loss in interference which again, the Loctite won't prevent. You need to stop whatever is causing the bearing to be loaded unevenly or just resign yourself to keeping a ready to go locker on the shelf to mitigate downtime.

Understood. Hard for me to imagine what would cause a 14 bolt to flex enough to cause it, but maybe the shave weakened the housing? I've not heard of this happening on other shaved 14 bolt setups, but my exposure is limited there. I do know that the axel was at least straight when I regeared last year. So, I'm still at a bit of a loss. I may pull it apart and measure it again to be sure.

 

[rasband]

I read @horsejockey61 's comment

Negative. With existing locker.

You realize Mike is Irish, right?

 

[gasiorv]

So the noise was coming from the carrier bearing surface spinning inside the bearing in lieu of the bearing spinning? Or from it not being perfectly concentric and the noise was coming from elsewhere? It sounds like a bearing going bad in the video, so i am surprised that you said the carrier bearing was good. I am assuming since you are getting a new locker that you will install it with new bearings.

 

[NashvilleTJ]

So the noise was coming from the carrier bearing surface spinning inside the bearing in lieu of the bearing spinning? Or from it not being perfectly concentric and the noise was coming from elsewhere? It sounds like a bearing going bad in the video, so i am surprised that you said the carrier bearing was good. I am assuming since you are getting a new locker that you will install it with new bearings.

Truthfully, I am not positive what what was making the noise, but the loose bearing was the only thing I see which is off. What is strange is that the noise consistently occurred at the same point is the rotation. If that bearing was the noise, and it was rotating, I’d think the noise would move in the rotation. I’ll get everything replaced and see what happens.

One thing, the carrier was definitely able to move back and forth by 14 thou…

 

[Woodrow]

Truthfully, I am not positive what what was making the noise, but the loose bearing was the only thing I see which is off. What is strange is that the noise consistently occurred at the same point is the rotation. If that bearing was the noise, and it was rotating, I’d think the noise would move in the rotation. I’ll get everything replaced and see what happens.

One thing, the carrier was definitely able to move back and forth by 14 thou…

Is your backlash the same in 4 quadrants? Watching the ring gear wobble in your video makes me ask.

 

[gasiorv]

Truthfully, I am not positive what what was making the noise, but the loose bearing was the only thing I see which is off. What is strange is that the noise consistently occurred at the same point is the rotation. If that bearing was the noise, and it was rotating, I’d think the noise would move in the rotation. I’ll get everything replaced and see what happens.

One thing, the carrier was definitely able to move back and forth by 14 thou…

Back and forth as in left and right or fwd and aft? I don't see how it would move left and right if it was shimmed right so I am assuming it is fwd and aft, up and down, all around. So if my assumption is correct and your shaft is out 0.022 then it would wobble with the shaft rotation and make the same noise every rotation.

I really don't understand how it is wobbling or moving 0.014 with the tight fit, I would think the bearing pushing on the carrier would keep it locked in place, how is it shimmed right if the bearing isn't seating fillet to fillet? Something has to be hitting

 

[gasiorv]

Hitting is a bad word, it typically means bad. So maybe this is better - there has to be contact between bearing inner race and carrier for it to shim tight.