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Re: [GMCnet] Got Double Trouble weighed at a CAT Scale [message #182625 is a reply to message #182405] Fri, 31 August 2012 16:05 Go to previous messageGo to previous message
GMC_LES is currently offline  GMC_LES   United States
Messages: 569
Registered: October 2009
Location: Montreal
Karma:
Senior Member
I have two complete frame assemblies and noticed several differences between them. My original frame is an early 75 unit (9/74) while my spare parts frame is from a 78 coach. The front frame clip is not fabricated the same on these two. The main differences are in where frame gussets and doubler plates have been installed but I also believe that the front frame clip is shaped differently behind the suspension mounting points. I'm wondering if anyone else has noticed these differences? I can photo document the differences if anyone is interested.

Les Burt
Montreal



On 2012-08-30, at 12:26 PM, Bill Bryant <bryant374@earthlink.net> wrote:

>
>
> Hi Dave,
>
> Here are the details for FRAME changes as I understand them:
>
> My sources are several Sales Brochures, 4 Parts Books & an Engineering presentation.
>
> Sales Brochures, Motor home:
>
> 1973 & 74
> Frame 6 x 2.50 x .125 SAE 950 side rails & SAE 1023 crossmembers.
>
> 1975
> Frame 6 x 2.50 x .125 SAE 1023 side rails SAE 950 crossmembers.
>
> 1977 & 78
> No mention
> (no attempt to correct the above conflicts)
>
> 1975 Transmode Sales Brochure:
>
> Frame SAE 950 for side rails & crossmembers.
>
>
> Operation "Conquest"
> June 14, 1974
> Introduction of Eleganza II and change of GVW from 11,200 to 11,700.
>
> 3 major changes identified:
> 1- Frame bogie-liner assy new crossmembers made of special alloy steel increased 50% in thickness. Suspension loads are evenly distributed throughout the structurd by the addition of alloy steel crossmember gussets.
>
> 2- Rear suspension working members redesigned (1 1/2" pins), development work began Nov. (1973), ended April (1974) after durability testing.
>
> 3- larger wheel bearings.
>
> Parts Books (printed Jan 1973 - May 1979)
> The first parts book, Jan.73 already showed new P/Ns issued for all crossmembers and all sections of the rear assembly section.
>
> 77Z (Sept. 76)
> Cross members changed again, reflecting those changes shown in the above Operation Conquest.
>
> Front diaginal brace added at 5V100542
>
> NOTE: TZEs prior to 5V100542 used a different P/N.
> QUESTION: Do any of you with earlier coaches have a frame WITHOUT the front digginal brace?
>
> No further frame changes noted after the June 76 77Z. The Z78 parts book shows the same P/N listing as the 77Z book.
>
>
>
>
>
>
>
>
>
>
>
>
> Re: [GMCnet] Got Double Trouble weighed at a CAT Scale
>
> Thu, 30 August 2012 08:13
>
>
> David Greenberg
>
>
> Bill didn't GM T&C add gussets to the 78 chassis to accommodate an increase?
>
>
>
> On Mon, Aug 27, 2012 at 8:07 PM, Bill Bryant <mailto:bryant374@earthlink.net> wrote:
>>
>>
>> -----Original Message-----
>> From: Bill Bryant
>>
>> Questions for the GMC Brain Trust:
>>
>> 1) Did GMC actually do anything to the suspension system to up the GAWR and GVWR or just "pencil whip it?"
>>
>> Rob,
>>
>> I am assembling some details on the 4 different GVWs used over the 6 years of production which will take me a little while (we have
>> company and they are distracting me).
>>
>> I can tell this much now:
>>
>> I was told by one of the original Engineers that one of the increases was a "paper" change made per Kurdt Stubenvoll, the others
>> resulted from changes in the product.
>>
>> The 4 different vintage parts books, Jan.1973 - 78Z show the same torsion bar part numbers for all years.
>>
>> --
>> Bill
>>>
>>>
>>
>>
>> I decided to consolidate some of the detail, sufficient for the posed question.
>>
>> GVWs
>> 1973 = 10,500
>> 1973 late = 11,200
>> 1975 = 11,700
>> 1978 = 12,500
>>
>> There were MANY changes spread throughout the production period, here are a few of those that likely apply to the GVW changes.
>>
>> 1973
>> Rear brakes, backing plate, spindle & bearings
>> front shocks and again in 1977
>>
>> Frame: Except for the side rails, all sections of the frame were changed at least once (1973 & ~75)
>>
>> Rear control arms, once for 1 1/4" bushings, once for 1 1/2" pins
>>
>> Front lower control arms changed 3 times.
>>
>> Radial tires & wheels @ 5V101674
>>
>> Body structure changed @ 6V100878 (body was part of frame/body load support design)
>>
>> As noted earlier, the same P/N torsion bar was used from
>> 1973 through 1978.
>>
>> There is probably more, but this should do for now.
>>
>>
>>
>>
>>
>>
>> --
>> Bill Bryant
>> 1976~PB
>> 1914 Ford
>> 1965 Corvette
>> GMC MH History CD
>> GMC Showroom Films DVD
>> http://bdub.net/billbryant/
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
>
>
> --
> David Lee Greenberg
> Port St Lucie, FL
> skype: david.lee.greenberg
>
>
> --
> Bill Bryant
> 1976~PB
> 1914 Ford
> 1965 Corvette
> GMC MH History CD
> GMC Showroom Films DVD
> http://bdub.net/billbryant/
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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Les Burt Montreal 1975 Eleganza 26ft A work in Progress

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