| Upper A-arm offset bushing [message #121372] |
Sat, 09 April 2011 04:56  |
midlf
Messages: 2212
Registered: July 2007
Location: SE Wisc. (Palmyra)
Karma: 1
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Senior Member |
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OK - I'm getting ready to put the bushings into the upper arms and I've collected a lot of information. Maybe too much but I'm missing one bit of info.
What I do have is that an offset bushing in the front should have the arrow pointing TOWARDS the ball joint.
An offset bushing in the rear should have the arrow pointing AWAY from the ball joint.
A picture of one of these MOOG busings is at:
http://www.gmcmhphotos.com/photos/showphoto.php?photo=38442
A picture of one of the offset bushings (NAPA) without an arrow is at:
http://www.gmcmhphotos.com/photos/showphoto.php?photo=38399
Comparing these two pictures shows that the "arrowhead" on an arrow-less bushing is the flat side of the rubber.
Another bit of passed on wisdom is that only one bushing is needed AND that using offset bushings in both the front and rear of the A-arm may interfere with with being able to set proper camber.
The one bit of info I don't have is, when using only one offset bushing, is it best to install it in the front or the back?
Another bit of info I recall reading, but don't have it marked or copied, is that camber should be very close to 0 or even negative. Is this correct?
Now - playing around with the arm it would appear that putting the offset bushing in the rear would enhance the setting of camber towards negative while installing it in the front would enhance camber towards positive. Does anyone have any thoughts or experience with this?
Also I note that the bushing I have do not have the end washers (shown in the picture of the MOOG bushing) that center the bolt in the bushing. I'm planning on sleeving the bushing and using Gr8 washers as needed to duplicate the function of the MOOG washers.
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
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| Re: Upper A-arm offset bushing [message #121378 is a reply to message #121372] |
Sat, 09 April 2011 07:34  |
C Boyd
Messages: 2629
Registered: April 2006
Karma: 18
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Senior Member |
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The one bit of info I don't have is, when using only one offset bushing, is it best to install it in the front or the back?
One offset in the rear.
Another bit of info I recall reading, but don't have it marked or copied, is that camber should be very close to 0 or even negative. Is this correct? yes
Now - playing around with the arm it would appear that putting the offset bushing in the rear would enhance the setting of camber towards negative while installing it in the front would enhance camber towards positive. Does anyone have any thoughts or experience with this?
setting the rear inward is more +
Also I note that the bushing I have do not have the end washers (shown in the picture of the MOOG bushing) that center the bolt in the bushing. I'm planning on sleeving the bushing and using Gr8 washers as needed to duplicate the function of the MOOG washers.
You will have to pry the old washers off the old bushings and press them on the new bushings after installing the new bushings with your vise.
[/quote]
C. Boyd
76 Crestmont
East Tennessee
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| Re: Upper A-arm offset bushing [message #121385 is a reply to message #121372] |
Sat, 09 April 2011 08:37 |
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mike miller
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
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Senior Member |
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| midlf wrote on Sat, 09 April 2011 02:56 |
OK - I'm getting ready to put the bushings into the upper arms and I've collected a lot of information. Maybe too much but I'm missing one bit of info.
What I do have is that an offset bushing in the front should have the arrow pointing TOWARDS the ball joint.
An offset bushing in the rear should have the arrow pointing AWAY from the ball joint.
A picture of one of these MOOG busings is at: ...
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I am not an expert, I haven't done this, BUT.... I read GMCnet.
I think you have it backwards. You want the upper ball joint to be moved to the rear of the coach.
I am sure a REAL expert will chime in.
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
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| Re: Upper A-arm offset bushing [message #121387 is a reply to message #121385] |
Sat, 09 April 2011 08:56 |
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mike miller
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
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Senior Member |
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| mike miller wrote on Sat, 09 April 2011 06:37 |
... I think you have it backwards. You want the upper ball joint to be moved to the rear of the coach.
I am sure a REAL expert will chime in.
|
After opening my (virtual) mouth I drew on some paper....
Never mind.... you had it right. front arrow to ball joint / back arrow away from ball joint WILL move the ball joint TOWARDS the rear of the coach.
The link Bob just posted says you only need one off-set bushing... it also agrees with you about the arrows.
Taking my foot out now.
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
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| Re: [GMCnet] Upper A-arm offset bushing [message #121388 is a reply to message #121387] |
Sat, 09 April 2011 09:32 |
Mr ERFisher
Messages: 7117
Registered: August 2005
Karma: 2
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Senior Member |
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I love the new settings from Lenzi
0,0,0, and all you can get on the caster.
now is that easy or what?
this table is old, and I think I will throw it away
http://gmcmotorhome.info/rear.html#settings
gene
On Sat, Apr 9, 2011 at 6:56 AM, Mike Miller <m000035@gmail.com> wrote:
>
>
> mike miller wrote on Sat, 09 April 2011 06:37
> > ... I think you have it backwards. You want the upper ball joint to be
> moved to the rear of the coach.
> >
> > I am sure a REAL expert will chime in.
>
> After opening my (virtual) mouth I drew on some paper....
>
> Never mind.... you had it right. front arrow to ball joint / back arrow
> away from ball joint WILL move the ball joint TOWARDS the rear of the coach.
>
> The link Bob just posted says you only need one off-set bushing... it also
> agrees with you about the arrows.
>
> Taking my foot out now.
> --
> Mike Miller -- Hillsboro, OR -- on the Black list
> '73 26' exPainted D. -- `78 23' Birchaven Rear Bath -- `77 23' Birchaven
> Side Bath
> http://m000035.blogspot.com
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
--
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] Upper A-arm offset bushing [message #121392 is a reply to message #121372] |
Sat, 09 April 2011 11:46 |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Senior Member |
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Steve,
RESPONSE INTERSPERSED BELOW IN CAPS FOR CALARITY.
Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Steve Southworth
Sent: Saturday, April 09, 2011 3:57 AM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Upper A-arm offset bushing
OK - I'm getting ready to put the bushings into the upper arms and I've
collected a lot of information. Maybe too much but I'm missing one bit of
info.
I HAD A QUICK CHAT WITH DAVE LENZI THIS MORNING TO MAKE SURE I'VE GOT ALL MY
BUSHINGS IN A ROW!
THE OBJECTIVE OF THE OFFSET BUSHINGS IS TO MOVE THE UPPER CONTROL ARM BALL
JOINT TOWARDS THE REAR OF THE COACH.
What I do have is that an offset bushing in the front should have the arrow
pointing TOWARDS the ball joint.
FORGET THE ARROW.
THE BOLT HOLE IN THE FRONT BUSHING SHOULD BE AS FAR AWAY FROM THE UPPER BALL
JOINT AS POSSIBLE.
An offset bushing in the rear should have the arrow pointing AWAY from the
ball joint.
FORGET THE ARROW!
THE BOLT HOLE IN THE REAR BUSHING SHOULD BE AS CLOSE TO THE UPPER BALL JOINT
AS POSSIBLE.
A picture of one of these MOOG busings is at:
http://www.gmcmhphotos.com/photos/showphoto.php?photo=38442
A picture of one of the offset bushings (NAPA) without an arrow is at:
http://www.gmcmhphotos.com/photos/showphoto.php?photo=38399
Comparing these two pictures shows that the "arrowhead" on an arrow-less
bushing is the flat side of the rubber.
Another bit of passed on wisdom is that only one bushing is needed AND that
using offset bushings in both the front and rear of the A-arm may interfere
with being able to set proper camber.
IT MAY OR MAY NOT HELP AND IT MAY OR MAY NOT HURT! HOW'S THAT FOR A
DEFINTIVE RESPONSE! ;-)
The one bit of info I don't have is, when using only one offset bushing, is
it best to install it in the front or the back?
IF YOU ARE GOING TO INSTALL ONE OFFSET BUSHING IT SHOULD BE PLACED IN THE
REAR "LEG" OF THE CONTROL ARM.
Another bit of info I recall reading, but don't have it marked or copied, is
that camber should be very close to 0 or even negative. Is this correct?
ALIGNMENT SETTINGS ARE:
TOE IN/OUT 0 INCHES - ERR IN THE TOE OUT DIRECTION; THE WHEELS WILL TOE IN
WHEN YOU ACCELERATE / UNDER POWER.
CAMBER = 0 DEGREES
CASTER - AS MUCH AS YOU CAN GET KEEPING THE CAMBER AT 0 DEGREES.
Now - playing around with the arm it would appear that putting the offset
bushing in the rear would enhance the setting of camber towards negative
while installing it in the front would enhance camber towards positive.
Does anyone have any thoughts or experience with this?
Also I note that the bushing I have do not have the end washers (shown in
the picture of the MOOG bushing) that center the bolt in the bushing. I'm
planning on sleeving the bushing and using Gr8 washers as needed to
duplicate the function of the MOOG washers.
YOU MUST HAVE THE END WASHERS, THEY TAKE UP SPACE IN BETWEEN THE BRACKETS
AND THE "LINES" CUT IN THEM HELP KEEP THE ADJUSTERS FROM MOVING.
FINAL NOTE, I SCREWED AROUND WITH OFFSET BUSHINGS IN DOUBLE TROUBLE AND TOM
HAMPTON DID A GREAT JOB SETTING THE CORRECT RIDE HEIGHT AND ALIGNMENT. THE
MOST CASTER HE COULD GET WAS 1.9 DEGREES ON BOTH SIDES AT 0 CAMBER.
COMPARING BEFORE AND AFTER WAS LIKE CHALK AND CHEESE! IT DROVE MUCH BETTER.
HOWEVER, AFTER HEARING FROM PEOPLE THAT HAD INSTALLED A PAIR OF DAVE LENZI'S
MODIFIED UPPER CONTROL ARMS I DECIDED TO GIVE A PAIR A GO. JOHN SHARPE AND I
INSTALLED THEM LAST YEAR BEFORE HELEN AND I BEGAN OUR SUMMER TOUR. I HAD IT
ALIGNED AND THEY SET 5 DEGREES CASTER, 0 CAMBER, AND ZERO TOE IN/OUT. DOUBLE
TROUBLE RIDES LIKE IT IS ON RAILS NOW. TRUCK PASS IN EITHER DIRECTION AND I
HARDLY FEEL IT. SIDE WINDS EFFECT IT MUCH LESS NOW ALSO.
ANYBODY ELSE WANT TO CHIME IN ABOUT DAVE'S UPPER CONTROL ARMS PLEASE DO SO!
--
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] Upper A-arm offset bushing [message #121414 is a reply to message #121388] |
Sat, 09 April 2011 19:08 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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Senior Member |
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Forget the arrows.
Use the offset on only the rear. Believe it or not, you'll achieve
more this way than doing it on both.
Having both off sets changes the camber to where it cancels the benefit.
Use the logic that the top ball joint need to move to the back for it
to get positive caster.
On Sat, Apr 9, 2011 at 7:32 AM, Mr.erf ERFisher <mr.erfisher@gmail.com> wrote:
> I love the new settings from Lenzi
>
> 0,0,0, and all you can get on the caster.
>
> now is that easy or what?
>
> this table is old, and I think I will throw it away
>
> http://gmcmotorhome.info/rear.html#settings
>
> gene
>
>
> On Sat, Apr 9, 2011 at 6:56 AM, Mike Miller <m000035@gmail.com> wrote:
>
>>
>>
>> mike miller wrote on Sat, 09 April 2011 06:37
>> > ... I think you have it backwards. Â You want the upper ball joint to be
>> moved to the rear of the coach.
>> >
>> > I am sure a REAL expert will chime in.
>>
>> After opening my (virtual) mouth I drew on some paper....
>>
>> Never mind.... you had it right. Â front arrow to ball joint / back arrow
>> away from ball joint WILL move the ball joint TOWARDS the rear of the coach.
>>
>> The link Bob just posted says you only need one off-set bushing... it also
>> agrees with you about the arrows.
>>
>> Taking my foot out now.
>> --
>> Mike Miller -- Hillsboro, OR -- on the Black list
>> '73 26' exPainted D. -- `78 23' Birchaven Rear Bath -- `77 23' Birchaven
>> Side Bath
>> http://m000035.blogspot.com
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
>
> --
> 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
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Unsubscribe or Change List Options:
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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