Ken,
A failed tooth on ring or pinion that locked up both, breaks the
half-shafts, and then shatters into bits?
We know the transmission didn't lock up, and that it is still driving the
speedometer, so any damage in the output shaft of the tranny is likely a
result rather than a cause. Can the spider lock up in a way that would
shear the shafts without locking up the FD input shaft? I have to think
you would have noticed that as a sudden jerk to the engine, not just a loss
of drive power.
How many miles on the final drive? Are the teeth on the 3.55 more fragile
than others, to get the ratio? Is your Caddy too strong (or should I say
"was", knowing that it is not at full compression at the moment?
Should we start stocking a few 1-ton-kit axle replacements on the East
Coast?
We are all trying to decide how likely it is that we will face such a
failure.
Rick "1-ton kit arriving momentarily" Denney
On Wed, Jul 19, 2017 at 7:10 PM Ken Henderson
wrote:
> I know Y'All are getting about all the fun you want out of this adventure
> of mine, but there's more to report: WIth so many unknowns -- surprises
> at every turn, SHE and I decided (SHE offered "HER SS pay") to have the
> coach towed home. Since I'd already used Allstate for this incident, I
> couldn't call and argue with them again. Because I've been expecting a
> "Excess Usage Cancellation Notice" from Allstate for years, I've got
> roadside service on my USAA auto insurance also -- for cheep. I called
> them, knowing nothing about their policies. They stated a maximum
> distance, over which I'd have to pay mileage. They quoted that overage at
> $800 for the 204 miles from Niceville, FL to Americus, GA. Instead, I went
> on Monday to the large towing service near me. They quoted $750 and to do
> the job on Tuesday.
>
> Accepting that, I returned to Niceville and spent the night in the coach.
> By the time the tow truck arrived just before noon, we had the coach
> pointed in the right direction on the side of FL Hwy 20. I won't go into
> the details here, but even after my face-to-face discussion with the owner
> of the tow service, who builds tow trucks, we were just barely able to
> devise a way to tow the GMC. They tell me that wheel lifts are falling out
> of favor -- bad news for us GMCers. At any rate, were home by 17:30, with
> the coach pushed onto the service rack with the Honda.
>
> After running errands, including paying the towing bill, I started in on
> the GMC:
>
>
> When I drained the FD lube, it was as black as engine oil after 10,000
> miles! When I got the cover off there was visible a big chunk out of one
> ring gear tooth and several smaller nicks -- no sign of the big chunk so it
> may have gotten chewed up. I didn't rotate the ring gear to look for other
> damage. Probably because I got distracted when I looked over at the inner
> passenger side CV joint -- it was sagging down, busted, just like the
> driver's side had been! When I saw the first one on Wednesday, I had no
> idea the other one could possibly be the same!
I'm tempted to erase
> that embarrrassing admission!
>
> I got that axle out, and a jig on my engine hoist attached to the FD. Then
> disconnected everything holding the FD in. I was too tired to lower it
> this evening, especially when I found that my custom Cad500 engine mount
> MAY interfere with removing the FD -- it's a matter of 1/8"-1/4",
> apparently. It's possible I may have to slide the transmission to the rear
> 1/2" or so to provide clearance. Not a real big deal, but an unexpected,
> unpleasant, PITA.
>
> This afternoon I got a note that Craig Lechowicz, JimK's FD rebuilder in
> MI, shipped my replacement FD today for delivery on Friday. Since two
> great GA GMC friends have offered to help, I've tentatively scheduled the
> FD Party for Monday. I'm expecting that we'll be able to do the test drive
> by late that afternoon, even if we have to replace the transmission
> (providing we learn that before cranking it).
>
> Also settled up with USAA, and already have $250 deposited to my USAA
> checking account. VERY fast, efficient, painless operation. I can't be
> too complimentary of either Allstate or USAA; they've treated me right and
> without any hassle.
>
> Wish us luck so that maybe I can close this too-long thread with one more
> posting -- a success report.
>
> Oh yeah, some final facts that some may find interesting: Both axles
> failed at the same location. The inner CV's are very similar to the OEM
> except that the three rotating balls and their bearings are retained on the
> ball carrier with circlips -- the umpty-leven needles can't fall out like
> on the OEM. Those ball assemblies are retained on the splined end of the
> shaft with a circlip on each side of the assembly. Both axles broke on the
> ball side (toward the inner end) at the circlip groove -- the base of that
> recess is obviously a stress riser, whether intentional or not. The big
> question now is what locked up and caused the instantaneous failures. The
> ring gear is rotating freely and each output shaft counter-rotates when the
> other is turned -- I had to secure the opposite output flange to loosen the
> 6 CV bolts.
>
> Here's a link to photos I took today. The passenger side shaft is nearest
> the camera:
>
>
https://drive.google.com/open?id=0B3XquSIYjDleQXZPNkFKVUNGRnM
>
> Ken H.
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--
Rick Denney
73 x-Glacier 230 "Jaws"
Off-list email to rick at rickdenney dot com
