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[GMCnet] Adjusting front ride height [message #220747] Sun, 01 September 2013 11:39 Go to next message
glwgmc is currently offline  glwgmc   United States
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I over stated how far off your is. A half inch side to side is not way off, it is just off and would be best to get it right. Adjusting ride height is an iterative process. Measure, adjust, drive two to five miles to fully settle the suspension, measure, adjust again, etc. until you get it right. Weight balance also plays a role so if you can, do a six wheel weigh and balance the load, especially side to side as best as you can even before the ride height check. While it has been covered many times in the past it is absolute, not relative ride height that is important. All of the things like the anti dive, cv joint alignment, etc. we're designed in at the absolute ride height specified. One can make a coach go straight down the road at just about any ride height, but everything will be off from the designer's intent at anything other than absolute ride height.

Download the Align it right! Presentation I gave at the GMCWS rally at Casa de Fruta, CA from the GMC page on my web site to find out why all this stuff matters so much.

Jerry
Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
Http://jerrywork.com
541-592-5360
Cell 541-499-1027
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Jerry & Sharon Work
78 Royale
Kerby, OR
Re: [GMCnet] Adjusting front ride height [message #220748 is a reply to message #220747] Sun, 01 September 2013 11:52 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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Sir: Since he lowered the high rear side to equal other side it should have allowed the opposite front corner to raise and get even closer to + - 1/4".


glwgmc wrote on Sun, 01 September 2013 12:39

I over stated how far off your is. A half inch side to side is not way off, it is just off and would be best to get it right. Adjusting ride height is an iterative process. Measure, adjust, drive two to five miles to fully settle the suspension, measure, adjust again, etc. until you get it right. Weight balance also plays a role so if you can, do a six wheel weigh and balance the load, especially side to side as best as you can even before the ride height check. While it has been covered many times in the past it is absolute, not relative ride height that is important. All of the things like the anti dive, cv joint alignment, etc. we're designed in at the absolute ride height specified. One can make a coach go straight down the road at just about any ride height, but everything will be off from the designer's intent at anything other than absolute ride height.

Download the Align it right! Presentation I gave at the GMCWS rally at Casa de Fruta, CA from the GMC page on my web site to find out why all this stuff matters so much.

Jerry
Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
Http://jerrywork.com
541-592-5360
Cell 541-499-1027
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C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] Adjusting front ride height [message #220750 is a reply to message #220748] Sun, 01 September 2013 12:13 Go to previous messageGo to next message
Jeff Marten is currently offline  Jeff Marten   United States
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What jack capacity and total lift is sufficient to raise the front end to remove the wheels, get jack stands under it at proper ride height so the rear height can be set? I'm not sure my 3-ton steel-body floor jack will get the job done. Also have a low profile 2-ton aluminum-body floor jack, but doubt there'd be room for both, plus jack stands on the cross member.

> To: gmclist@temp.gmcnet.org
> From: covered-wagon@comcast.net
> Date: Sun, 1 Sep 2013 11:52:48 -0500
> Subject: Re: [GMCnet] Adjusting front ride height
>
>
>
> Sir: Since he lowered the high rear side to equal other side it should have allowed the opposite front corner to raise and get even closer to + - 1/4".
>
>
> glwgmc wrote on Sun, 01 September 2013 12:39
> > I over stated how far off your is. A half inch side to side is not way off, it is just off and would be best to get it right. Adjusting ride height is an iterative process. Measure, adjust, drive two to five miles to fully settle the suspension, measure, adjust again, etc. until you get it right. Weight balance also plays a role so if you can, do a six wheel weigh and balance the load, especially side to side as best as you can even before the ride height check. While it has been covered many times in the past it is absolute, not relative ride height that is important. All of the things like the anti dive, cv joint alignment, etc. we're designed in at the absolute ride height specified. One can make a coach go straight down the road at just about any ride height, but everything will be off from the designer's intent at anything other than absolute ride height.
> >
> > Download the Align it right! Presentation I gave at the GMCWS rally at Casa de Fruta, CA from the GMC page on my web site to find out why all this stuff matters so much.
> >
> > Jerry
> > Jerry Work
> > The Dovetail Joint
> > Fine furniture designed & hand crafted
> > in the 1907 former Masonic Temple building
> > in historic Kerby, OR
> > Http://jerrywork.com
> > 541-592-5360
> > Cell 541-499-1027
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
>
> --
> C. Boyd
> 76 Crestmont
> East Tennessee
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1985 Gulf Stream 34' Sun Stream 1964 Falcon 'Vert 1980 Bradley GTE 1999 Chevy Tahoe 2005 Saab 93 Aero 1987 Suzuki Intruder 1400 1978 Glastron/Carlson CV23
Re: [GMCnet] Adjusting front ride height [message #220804 is a reply to message #220750] Sun, 01 September 2013 20:00 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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The 2Ton Al jack will not survive lifting service on a GMC. Too light weight. I had one self-destruct lifting an empty GMC shell at Dave Silva's. The actual hydraulic cylinder exploded, metal everywhere. Unsupported GMC's hit the ground very fast.
For lifting the front end, I use a 6 ton bottle jack, with jack stands under the crossmember. Lift a little adjust the jack stand, and repeat until it is at the height you need. Place the bottle jack in the center of the crossmember.(near the two holes).
After removing the wheels, I also slide them under the frame as a final support in case of extreme failure of both the bottle jack and the jack stands.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] Adjusting front ride height [message #220816 is a reply to message #220804] Sun, 01 September 2013 22:22 Go to previous messageGo to next message
noi is currently offline  noi   United States
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tphipps wrote on Sun, 01 September 2013 18:00

The 2Ton Al jack will not survive lifting service on a GMC. Too light weight. I had one self-destruct lifting an empty GMC shell at Dave Silva's.


Tom,

Could you post some more details (brand/model/age) on the 2ton floor jack failure?

I find it troubling that an empty shell could weigh enough to cause a 2ton floor jack, even low cost one, to “explode”! – My empty shell weighs about 1200lb total and no one “corner” more than 500lb…. Well within the stated carrying capacity of the 1.5ton HF/Al floor jack I have been using.

Though I never raise any one “corner” more than a 4x4 height, or one “notch” on the jack stand, at a time - I will be getting a larger one later, that has the full GMC weight carrying capacity, when it is needed.

Thanks,

Carl P.
76 Birchaven
South of Fremont
Re: [GMCnet] Adjusting front ride height [message #220818 is a reply to message #220747] Sun, 01 September 2013 23:55 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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The entire front end weighs between 3900 and 4300 pounds. We weighed a bunch of GMCs at several rallies a while back. The average one is right near 4000 pounds. I use a single 5000 or 6000 pound (I forget it's rating) long reach floor jack all the time on mine. In fact mine is sitting up on the jack right now the way I left it two days ago in my hangar. I need to go back an do some more work on it in the next day or two.

A couple a jack stands under the frame or the cross member is required insurance in case the jack ever should quit.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Adjusting front ride height [message #220849 is a reply to message #220818] Mon, 02 September 2013 09:44 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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I lift the front of my coach (4200#) with a single CCV (HF) 3-ton floor jack. I do not like the jack, but my 50yo 3
000# Hein-Werner won't lift it. It will lift a bogie.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Adjusting front ride height [message #220856 is a reply to message #220849] Mon, 02 September 2013 10:02 Go to previous messageGo to next message
sgltrac is currently offline  sgltrac   United States
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My 10 year old Mac 2.5 ton jack will pick the whole front up easily and repeatedly. Closely chased by jack stands every available click.

Todd Sullivan

Sully
77 royale
Seattle

On Sep 2, 2013, at 7:44 AM, Matt Colie <matt7323tze@gmail.com> wrote:

>
>
> I lift the front of my coach (4200#) with a single CCV (HF) 3-ton floor jack. I do not like the jack, but my 50yo 3
> 000# Hein-Werner won't lift it. It will lift a bogie.
>
> Matt
> --
> Matt & Mary Colie
> '73 Glacier 23 Chaumière (say show-me-air)
> Now with 4 working Rear Brakes
> SE Michigan - Twixt A2 and Detroit
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Sully 77 Royale basket case. Future motorhome land speed record holder(bucket list) Seattle, Wa.
Re: [GMCnet] Adjusting front ride height [message #220857 is a reply to message #220849] Mon, 02 September 2013 10:03 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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To insure a decent safety margin, I would think that a minimum of a 3 ton
steel floor jack should be used when lifting the whole front of the coach.
I personally use 6 ton jack stands under the side frame rails where the
front clip is bolted to the side rails. DO NOT UNDER ANY CIRCUMSTANCES
CRAWL UNDER A COACH THAT IS ONLY SUPPORTED BY A HYDRAULIC JACK. THERE ARE
NO SECOND CHANCES IN THAT SCENARIO IF THE JACK FAILS OR THE PAD SLIPS OFF
THE SLIPPERY CROSSMEMBER. IT CAN AND WILL KILL YOU. Terry Skinner makes a
support pad that indexes with the two holes in the front crossmember that
gives a jack a great support base. If you are raising the coach with a
bottle jack, it is a must have piece.
Jim Hupy
Salem, OR
78 GMC Royale 403


On Mon, Sep 2, 2013 at 7:44 AM, Matt Colie <matt7323tze@gmail.com> wrote:

>
>
> I lift the front of my coach (4200#) with a single CCV (HF) 3-ton floor
> jack. I do not like the jack, but my 50yo 3
> 000# Hein-Werner won't lift it. It will lift a bogie.
>
> Matt
> --
> Matt & Mary Colie
> '73 Glacier 23 Chaumière (say show-me-air)
> Now with 4 working Rear Brakes
> SE Michigan - Twixt A2 and Detroit
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Adjusting front ride height [message #220868 is a reply to message #220750] Mon, 02 September 2013 10:24 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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Registered: April 2006
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Senior Member
I use a 3 1/2 ton Craftsman floor jack with the GMC pad on it. It creeks and pops but works. 6 ton heavy duty American made Jack stands. I have bent 3 ton cheepie jack stands that were under the rear of my 55 Chevy. Not near the weight of the GMC.



[quote title=Jeff Marten wrote on Sun, 01 September 2013 13:13]What jack capacity and total lift is sufficient to raise the front end to remove the wheels, get jack stands under it at proper ride height so the rear height can be set? I'm not sure my 3-ton steel-body floor jack will get the job done. Also have a low profile 2-ton aluminum-body floor jack, but doubt there'd be room for both, plus jack stands on the cross member.


C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] Adjusting front ride height [message #220963 is a reply to message #220818] Mon, 02 September 2013 21:58 Go to previous message
noi is currently offline  noi   United States
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Ken Burton wrote on Sun, 01 September 2013 21:55

The entire front end weighs between 3900 and 4300 pounds. We weighed a bunch of GMCs at several rallies a while back. The average one is right near 4000 pounds. I use a single 5000 or 6000 pound (I forget it's rating) long reach floor jack all the time on mine. In fact mine is sitting up on the jack right now the way I left it two days ago in my hangar. I need to go back an do some more work on it in the next day or two.

A couple a jack stands under the frame or the cross member is required insurance in case the jack ever should quit.


Ken,

Thanks for the clarification about the Tom’s floor jack failure – When he said “empty GMC shell”, I took that at face value and thought he meant just the shell by itself with nothing in it and not attached to the steel frame – I was perplexed by how an empty shell could weigh so much that it would “explode” a 2ton floor jack!

Thanks to everyone on their thoughts about the properly sized/placed floor jack info.

Carl P.
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