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Re: [GMCnet] Final Drive Intermediate Axle questions [message #322538 is a reply to message #322533] Wed, 23 August 2017 09:59 Go to previous messageGo to previous message
Kosier is currently offline  Kosier   United States
Messages: 834
Registered: February 2008
Karma:
Senior Member
Rick,

Here's all the info as best can find. The brace is GM part #397480. In
the thru-75
Cadillac parts manual it is listed as fitting 68-75 Eldos. Oddly enough,
the bolt for
the end is listed as 67-75. In the 76-81 parts manual, there is no mention
of the
brace, although I know it was used on at least 76-78. I have a half-dozen
RH output
shafts and the Cadillac brackets have a mounting ear for the brace while the
Olds
brackets have none. I do have a shaft for an Olds 3.21 and it's different,
but not like
the Caddy. So I will conclude you never had the brace.

Gary Kosier who's almost as pedantic as Rob Mueller
77PB w/500Cad
Newark, Ohio

--------------------------------------------------
From: "Richard Denney"
Sent: Wednesday, August 23, 2017 9:50 AM
To:
Subject: Re: [GMCnet] Final Drive Intermediate Axle questions

> I don't know if I have the threaded hole. I'm not visualizing it
> immediately, but it would seem to me that the 3.21 was only made during
> the
> time that both Cadillac and Oldsmobile used it (based on Rob's data), so I
> would have thought they all had it. I don't recall an unused threaded
> hole,
> but I wasn't looking for one, either.
>
> I was planning to use a piece of 1/8" flat bar. It seems to me that if
> tightened the bracket causes that bar to be insufficient (or maybe to need
> the thing in the first place), the bracket needs to be straightened. Given
> that GM decided it wasn't needed, I'd prefer not to use it except to
> identify the problem.
>
> Rick "FD is an hour away until the weekend" Denney
>
> On Wed, Aug 23, 2017 at 8:36 AM, Ken Henderson
> wrote:
>
>> Darned if I know how I wound up with the brace on mine -- the facts are
>> lost somewhere in my now-murky past. I know I wasn't surprised to find
>> it,
>> so at some time or another I saw one and thought I was supposed to have
>> one.
>>
>> AFAIK before getting under the coach, there's only one place to
>> measure --
>> from the hole in the bracket to the threaded hole in the FD. Question
>> is,
>> do you have the hole in the FD?
>>
>> As far as the profile of the brace, it's basically straight except for
>> the
>> 90* bend at the bracket end. It's not flat stock but stamped to provide
>> greater rigidity with thinner material. I'd probably use 1/4" bar stock
>> if
>> I were making one (though 1/8" might be enough).
>>
>> I'll get to the shop after breakfast.
>>
>> Ken
>>
>>
>> On Wed, Aug 23, 2017 at 8:17 AM, Richard Denney
>> wrote:
>>
>>> I wonder if Gary (or Manny) has one lying around in his stash. Seems a
>> lot
>>> of trouble to remove one just to measure it.
>>>
>>> Given that this strut only appeared on Eldorados, and given that only
>>> (some) Eldorados used the 3.21, and given that the shaft is different
>> with
>>> that FD, I wonder if the struts are the same for the 455 application.
>>> Do
>> we
>>> know that the blocks have the same width across those mounting points?
>>> Manny tells me the brackets are the same, but I see an extra mounting
>> hole
>>> for that strut in the picture I linked, so I suspect that Cadillac
>> dropped
>>> the use of this strut just like GMC did for the motorhome. I know that
>> the
>>> 3.21 has been used pretty routinely with 455's, but I've never heard
>>> talk
>>> of this strut before.
>>>
>>> Maybe if you could measure the critical distance between the bracket
>>> and
>>> some reliable point on the final drive, I could use that to validate
>>> the
>>> straightness of the bracket once installed. If the measurement is
>> correct,
>>> then there is no need for the strut, it seems to me. My suspicion is
>>> they
>>> used it for a while and then decided it wasn't really necessary.
>>>
>>> How in the world did you end up with one on your motorhome? Have you
>> always
>>> had it? I don't see any hint of it in X-7425, looking at Figure 4, Page
>>> 3C-4.
>>>
>>> I won't be back at the coach until tomorrow night at the earliest, or
>>> probably Friday night or Saturday morning. (The grass still needs to be
>>> mowed and the coach is an hour away.) If I can't get this resolved
>>> immediately, I'm going to do other things (like putting in the front
>>> end,
>>> and dropping the tanks) while this waits for resolution. I'm going to
>> give
>>> Manny a call today to discuss it. But I need to have this all done by
>> Labor
>>> Day weekend, and I'm traveling next week and the following week.
>>>
>>> Rick "a little early in San Jose" Denney
>>>
>>>
>>>
>>> On Wed, Aug 23, 2017 at 7:49 AM, Ken Henderson
>>> wrote:
>>>
>>>> Yep, the 6.056 brace is the one I was talking about.
>>>>
>>>> Might know we'd have to have Gary to explain it.
>>>>
>>>> While your problem is obviously more fundamental than that, it may be
>>> worth
>>>> the minor effort to fabricate and install one. If it helps, at least
>> it
>>>> may give you a clue to the correct solution.
>>>>
>>>> Do you want me to remove mine and measure it for you?
>>>>
>>>>
>>>> Ken H.
>>>>
>>>>
>>>> On Tue, Aug 22, 2017 at 11:36 PM, Richard Denney
>>>> wrote:
>>>>
>>>> > With that clue, I found this:
>>>> >
>>>> > http://www.caddydaddy.com/1967-1969-cadillac-eldorado-
>>>> > final-drive-output-shaft-flange-front-drive-axle.html
>>>> >
>>>> > The bracket I have doesn't have a hole for the outboard end of that
>>>> strut,
>>>> > although it looks like it uses one of the retainer bolts plus an
>>>> additional
>>>> > alignment bolt.
>>>> >
>>>> > Rick "wondering if this could be fabricated" Denney
>>>> >
>>>> > On Tue, Aug 22, 2017 at 11:08 PM Gary Kosier
>>>> > >>
>>>> > wrote:
>>>> >
>>>> > > Rick,
>>>> > > ''It's because that strut is only used on the Eldorado.
>>>> > >
>>>> > > Gary Kosier
>>>> > > 77PB w/500Cad
>>>> > >
>>>> > --
>>>> > Rick Denney
>>>> > 73 x-Glacier 230 "Jaws"
>>>> > Off-list email to rick at rickdenney dot com
>>>> > _______________________________________________
>>>> > GMCnet mailing list
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>>>> >
>>>> _______________________________________________
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>>>>
>>>
>>>
>>>
>>> --
>>> '73 X-Glacier 230 "Jaws"
>>> Northern Virginia
>>> Offlist email: rick at rickdenney dot com
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
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>>>
>> _______________________________________________
>> GMCnet mailing list
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>
>
>
> --
> '73 X-Glacier 230 "Jaws"
> Northern Virginia
> Offlist email: rick at rickdenney dot com
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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