TCase issues/potentially solved

Ddays

Hooked
So my Tcase issues are fairly common I guess. Two cracked cases are enough for a lifetime. I could never really figure out why this happened, especially the grenaded one.
I was at the shop checking on the progress of the axle install today and happened to look at the Tcase that just got taken out. Matt, the mechanic showed me something that I'm now pretty sure has been the issue all along.
So on the Tcase drive flange, the nut that holds it on has a wide flange on it. An o-ring gets compressed in a recess and that seals off the fluid.

20200520_170610_resized.jpg
20200520_170618_resized.jpg
20200520_170641_resized.jpg


But the nuts that were holding the flanges onto the tcase weren't wide enough to stay up out of the recess - instead they fit inside the recess and compressed the oring seal onto the splined shaft AND NEVER SEATED AGAINST ANY METAL. It always had a cushion between fully seating that more than likely allowed the flanges to wobble slightly and created a vibration that caused the cases to fail.

See how it doesn't sit up on the recess, rather it fits inside it.

20200520_170628_resized.jpg


So even though I had both shafts balanced (twice) new Ujoints, caster set at 6* etc, etc, the shafts must have been wobbling enough to cause failure. The new Rubi case has nuts with larger shoulders that sit on top of the flange instead of inside it. I really hope this solves the issue. Well, having lockout hubs helps too, but still. Check your nuts!
 
So where did the wrong nut come in to play? How did it get put on in the first place?

Sent from my SM-S506DL using WAYALIFE mobile app

That's the mystery at the moment. Both the front & rear flanges had them installed. I thought possibly I did it but I looked in my spares because I keep all of that shit just in case & they're not anywhere to be found.
 
Glad you found a likely suspect.

Hopefully that means your troubles are over.

Where is this located. It's hard to tell from the close up picture
 
Good catch Jerry, not sure if your supposed to but I reused the original nut and oring, put a bunch of rtv on the oring and red locktite on the shaft threads. Better get some bigger nuts buddy [emoji23]


Sent from my iPhone using WAYALIFE mobile app
 
Glad you found a likely suspect.

Hopefully that means your troubles are over.

Where is this located. It's hard to tell from the close up picture

These are the nuts that hold the drive flanges/yokes onto the Tcase output shafts, both front and rear.

s-l1600.jpg
 
So my Tcase issues are fairly common I guess. Two cracked cases are enough for a lifetime. I could never really figure out why this happened, especially the grenaded one.
I was at the shop checking on the progress of the axle install today and happened to look at the Tcase that just got taken out. Matt, the mechanic showed me something that I'm now pretty sure has been the issue all along.
So on the Tcase drive flange, the nut that holds it on has a wide flange on it. An o-ring gets compressed in a recess and that seals off the fluid.


But the nuts that were holding the flanges onto the tcase weren't wide enough to stay up out of the recess - instead they fit inside the recess and compressed the oring seal onto the splined shaft AND NEVER SEATED AGAINST ANY METAL. It always had a cushion between fully seating that more than likely allowed the flanges to wobble slightly and created a vibration that caused the cases to fail.

See how it doesn't sit up on the recess, rather it fits inside it.


So even though I had both shafts balanced (twice) new Ujoints, caster set at 6* etc, etc, the shafts must have been wobbling enough to cause failure. The new Rubi case has nuts with larger shoulders that sit on top of the flange instead of inside it. I really hope this solves the issue. Well, having lockout hubs helps too, but still. Check your nuts!

Yeah, I could totally see how that could be the culprit. Glad you finally got this figured out.
 
Damn. Now you have me nervous as I’m 95% positive the size of the two flange nuts I have are different between the front and rear on the transfer case. I know for a fact they were in the driveshafts I just installed for a friend a few weeks ago because I mentioned it while putting RTV on when installing them.
 
Yeah, I could totally see how that could be the culprit. Glad you finally got this figured out.

And now that that's been taken care of, I'm extra happy I didn't spend the money on an Atlas case. :crazyeyes:

Damn. Now you have me nervous as I’m 95% positive the size of the two flange nuts I have are different between the front and rear on the transfer case. I know for a fact they were in the driveshafts I just installed for a friend a few weeks ago because I mentioned it while putting RTV on when installing them.

I'd grab a flashlight & check. If they fit inside I'd get larger nuts.
 
That's the mystery at the moment. Both the front & rear flanges had them installed. I thought possibly I did it but I looked in my spares because I keep all of that shit just in case & they're not anywhere to be found.

If memory serves me the smaller flange nuts are for direct yolks instead of the flange type. Only variance I can think of.


Sent from my iPad using WAYALIFE
 
Nuts aren't supposed to go all the way in are they? :thinking:

I guess if you’re into that sort of thing 🤷*♀️.

Those are aftermarket flanges correct. I just changed mine about a month ago, I’ll have to get under there and look now.
 
I guess if you’re into that sort of thing 🤷*♀️.

Those are aftermarket flanges correct. I just changed mine about a month ago, I’ll have to get under there and look now.

Actually a good question. With Adams driveshafts you move flanges around and re-use certain pieces. Could a mismatch there be causing this
 
Top Bottom