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A few general questions [message #99673] Tue, 14 September 2010 00:05 Go to next message
Peter_Crowl is currently offline  Peter_Crowl   United States
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The Operators Manual says not to tow anything over 1,000 pounds.
Yet toads are towed. Are there necessary mods for this?

Where should I look for the dreaded frame rust?

What's the deal with the two tanks one filler setup?

I seem to have 3 water inlets - One in the power cord bay and two others...I get that one's gravity fill for the potable tank and one's a city water hookup - what's the third? I didn't see a third in the manual.

More - I'm sure - as I get deeper into it :~)

Peter
in Denver
Re: A few general questions [message #99676 is a reply to message #99673] Tue, 14 September 2010 00:36 Go to previous messageGo to next message
zhagrieb is currently offline  zhagrieb   United States
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Location: Portland Oregon
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I too have a third water connection. It's on the drivers side below the galley window and was plumbed into the sink drain. I never was sure what its purpose was other than to perhaps flush the sewer tank.

One owner tows an enclosed 24 foot box trailer with bodatious restored Chevy inside. He says it weight about 7000 lb. I know of no mods necessary to enable this kind of tow other than a frame hitch.

The one fuel filler feeds both tanks through a T. Sometimes it works, sometime not. Venting while filling seems to be an ongoing problem often preventing the tanks from filling completely.

There was a recent post here showing many Craig's listings of GMC's for sale if you want to look around.

Welcome,

Glenn


Glenn Giere, Portland OR, K7GAG '73 "Moby the Motorhome" 26'
Re: [GMCnet] A few general questions [message #99680 is a reply to message #99673] Tue, 14 September 2010 00:58 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   United States
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You can tow plenty more than that - no idea what the limit is...

Frame rust generally occurs at the bogies (rear wheel suspension) are where the frame doubles-up.

Never get under the back of your coach without supports - jack stands, or similar.

Forget the idea that we have two tanks. We have a two celled 50 gallon tank. The cells are connected and for the most part act as one tank. Gene Fisher has some great information about the tanks (really just about everything) on his site www.gmcmotorhome.info

Get your fingernails dirty and have some fun. There is a reason you've always like these coaches!

Larry Davick
The Mystery Machine
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: [GMCnet] A few general questions [message #99681 is a reply to message #99680] Tue, 14 September 2010 01:56 Go to previous messageGo to next message
peter bailey is currently offline  peter bailey   United States
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Location: Gawler, South Australia
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Another source of frame rust is where the rear frame ( part of it the bumper
is attached to) rails both sides attach (with bolts) to the main frame
rails.
Sure sign of rust where the frame doubles holding the bogies is undulation
of the lower returns of the channel main frame (wavy appearance looking
along the frame at the very bottom). I am led to believe that this is caused
by whatever snow or water freezing to ice and in doing so expands, I don't
know if that is correct just something that I had been told. Where I live it
never snows or freezes so I tend to believe what I am told.
Peter Bailey
from Ozy Aussie
----- Original Message -----
From: "Larry Davick" <ljdavick@comcast.net>
To: <gmclist@temp.gmcnet.org>
Sent: Tuesday, September 14, 2010 3:28 PM
Subject: Re: [GMCnet] A few general questions


> You can tow plenty more than that - no idea what the limit is...
>
> Frame rust generally occurs at the bogies (rear wheel suspension) are
> where the frame doubles-up.
>
> Never get under the back of your coach without supports - jack stands, or
> similar.
>
> Forget the idea that we have two tanks. We have a two celled 50 gallon
> tank. The cells are connected and for the most part act as one tank.
> Gene Fisher has some great information about the tanks (really just about
> everything) on his site www.gmcmotorhome.info
>
> Get your fingernails dirty and have some fun. There is a reason you've
> always like these coaches!
>
> Larry Davick
> The Mystery Machine
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] A few general questions [message #99683 is a reply to message #99673] Tue, 14 September 2010 03:32 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
>
> What's the deal with the two tanks one filler setup?
>
> here is some reading
http://gmcmotorhome.info/tank.html

gene



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] A few general questions [message #99691 is a reply to message #99683] Tue, 14 September 2010 08:02 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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We began towing our 2700 pound, dry weight, Vibe gt with stock 307 gears. That was fine out here in the midwest. When we started negotiating the Rockies we changed that to 355. We have never had any problems towing.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: A few general questions [message #99693 is a reply to message #99673] Tue, 14 September 2010 08:14 Go to previous messageGo to next message
Tom Lins is currently offline  Tom Lins   United States
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Registered: February 2004
Location: St Augustine, FL
Karma: 1
Senior Member
Peter_Crowl wrote on Tue, 14 September 2010 01:05

The Operators Manual says not to tow anything over 1,000 pounds.
Yet toads are towed. Are there necessary mods for this?

Where should I look for the dreaded frame rust?

What's the deal with the two tanks one filler setup?

I seem to have 3 water inlets - One in the power cord bay and two others...I get that one's gravity fill for the potable tank and one's a city water hookup - what's the third? I didn't see a third in the manual.

More - I'm sure - as I get deeper into it :~)

Peter
in Denver


We tow a 4300 lb Jeep without any problems with 3.21 gearing.



Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel
Manuals on DVD
YOUTUBE Channel: GMC Dealer Training Tapes
http://www.bdub.net/tomlins/
Re: [GMCnet] A few general questions [message #99711 is a reply to message #99683] Tue, 14 September 2010 09:39 Go to previous messageGo to next message
Peter_Crowl is currently offline  Peter_Crowl   United States
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Ah Ha!
Thanks Gene - and thanks to all!
That's what I needed. I was thinking it might be a Reserve Tank setup like the early VW's used -two different pickups in the same tank - but this is much more interesting Rolling Eyes

Now I know why it was running so rough up hills coming home. The seller said he'd put 10 gallons in it so I knew I should have enough to get home...but not in this scenario. I ran out as I pulled into a gas station Shocked

Rust at the bogeys - ok - I'll get out and get under they used to say - or actually sing. It would be nice if I could get it up on my lift but it's only 10,000# capacity.

Towing - it looked like it's done...I have 3.07 gears per my build sheet - and I'm in the Mountain West. Most of my travel is toward the East though. I guess we'll see how it goes. I'm regreting selling my Moggie (Morris Minor) - would have been a terrific dinghy!

Peter
in Denver


Re: [GMCnet] A few general questions [message #99714 is a reply to message #99711] Tue, 14 September 2010 09:53 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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One thing that frequently occurs on the GMC is that fuel can and does
frequently travel between the two tanks via the filler manifold. Steep
downhills can transfer enough fuel when you are low on fuel to uncover the
fuel pickup tube in the rear {main} tank and the engine will quit. When that
happens, one gets a first hand lesson in "How to steer and brake a GMC
without power assist" while driving. Keeping the tanks above 1/4 full if
possible will help prevent this from happening. I have a really steep
driveway descending towards my shop where I store My Coach. I have about 4"
clearance between the mirrors and the edge of my shop door on each side of
the coach. That is when I learned about this quirk. White knuckle time for
sure.
Jim Hupy
Salem, Or
78 Royale 403

On Tue, Sep 14, 2010 at 7:39 AM, Peter Crowl <Finboats@gmail.com> wrote:

>
>
> Ah Ha!
> Thanks Gene - and thanks to all!
> That's what I needed. I was thinking it might be a Reserve Tank setup like
> the early VW's used -two different pickups in the same tank - but this is
> much more interesting :roll:
>
> Now I know why it was running so rough up hills coming home. The seller
> said he'd put 10 gallons in it so I knew I should have enough to get
> home...but not in this scenario. I ran out as I pulled into a gas station
> 8o
>
> Rust at the bogeys - ok - I'll get out and get under they used to say - or
> actually sing. It would be nice if I could get it up on my lift but it's
> only 10,000# capacity.
>
> Towing - it looked like it's done...I have 3.07 gears per my build sheet -
> and I'm in the Mountain West. Most of my travel is toward the East though. I
> guess we'll see how it goes. I'm regreting selling my Moggie (Morris Minor)
> - would have been a terrific dinghy!
>
> Peter
> in Denver
>
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: A few general questions [message #99723 is a reply to message #99673] Tue, 14 September 2010 10:28 Go to previous messageGo to next message
mike miller   United States
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Location: Hillsboro, Oregon
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Senior Member
Peter_Crowl wrote on Mon, 13 September 2010 22:05

The Operators Manual says not to tow anything over 1,000 pounds.
Yet toads are towed. Are there necessary mods for this?
...

I seem to have 3 water inlets ...


Towds are different from trailers as they do not really have tongue weight. BUT, I think the 1000lb limit had more to do with brakes than anything else. Toad brakes are a good thing and you should have them on any towd... especially when much over 2000lbs.

3 water inlets: I suspect you have found a PO (Previous Owner) added feature.


Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com
Re: [GMCnet] A few general questions [message #99832 is a reply to message #99711] Tue, 14 September 2010 22:22 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
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Senior Member
Peter,
You can pull anything for so long before you'll pay the price.
3.07 on a tire size that we run does not work without stressing the
transmission and lugging the engine. The Torque of the engine does not kick
in till your going 65-70.
Even the final drive takes a beating with the load from the high torque
engine.
We have supplied almost 3,000 customers with 3.55/3.70 and 12 with4.10 gear
assembly.
They tell us that the gears were the only item they found that gave them
more power without sacrificing on mileage.
I personally run a 540 Cad and find that we do best with a 3.70. I use to
run 3.55, but feel the lower ratio is lot better when we run slow speeds
around 50-60.
Back in 1982 I ran a 3.21 and hardly noticed any gain.




>
>
>
>
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
>
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] A few general questions [message #99837 is a reply to message #99832] Tue, 14 September 2010 23:07 Go to previous messageGo to next message
Peter_Crowl is currently offline  Peter_Crowl   United States
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Hi Jim,
Your reputation preceeded you :~)

So what does it cost to change the gear set?

Peter
Re: [GMCnet] A few general questions [message #99879 is a reply to message #99837] Wed, 15 September 2010 09:56 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
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Senior Member
They are on our website, along with a chart so you can see what it does for
you.
If you have questions, call me o our toll free line.

On Tue, Sep 14, 2010 at 9:07 PM, Peter Crowl <Finboats@gmail.com> wrote:

>
>
> Hi Jim,
> Your reputation preceeded you :~)
>
> So what does it cost to change the gear set?
>
> Peter
> _______________________________________________
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>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] A few general questions [message #99883 is a reply to message #99832] Wed, 15 September 2010 10:17 Go to previous message
WD0AFQ is currently offline  WD0AFQ   United States
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Location: Dexter, Mo.
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Senior Member

I personally run a 540 Cad and find that we do best with a 3.70. I use to
run 3.55, but feel the lower ratio is lot better when we run slow speeds
around 50-60.
Back in 1982 I ran a 3.21 and hardly noticed any gain.


> Jim Kanomata
> Applied/GMC, Fremont,CA


[/quote]


Of course Jim is kidding. He never runs that speed except when he is accelerating to his normal 80-85 mph. I know. Ran 1000 miles with him. Only time he ran less than 75-80 mph was when I was in the lead and hogging center line so he could not pass. Grace thanked me over and over.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
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