Home » GMC » GMCnet » Front height adjustment
| Front height adjustment [message #168220] |
Tue, 01 May 2012 22:08  |
 gbarrow
Messages: 397
Registered: February 2004
Location: Lake Almanor, Ca. |
Senior Member |
|
|
In a recent thread about adjusting front ride height a member stated that he had been able to make adjustments without the use of a tool to relieve the pressure on the pork chop. He accomplished this by merely jacking up the coach and taking the weight off the front wheels.
I would like to read the thread again but I can't find it.
Any one out there remember the post or member who posted it?
Thanks
Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
|
|
|
| Re: [GMCnet] Front height adjustment [message #168223 is a reply to message #168220 ] |
Tue, 01 May 2012 22:42  |
Robert Mueller
Messages: 9201
Registered: July 2007
Location: Sydney, Australia |
Senior Member |
|
|
Gene,
That is correct; HOWEVER, the Maintenance Manual specifically says not to
screw the bolts in to adjust the ride height.
Reference Maintenance Manual X-7525 Page 3A-20
NOTE: Never attempt to increase the ride height of the vehicle using the
adjusting bolt only, (figure 30). The bolt will turn but will strip the
threads and will necessitate replacement of the bolt. Always use the special
tool.
Now there will be comments that "they" take the weight off the coach and do
it all the time without any problems. I am happy that "they" have been
successful I am merely advising what the guys that designed and built the
GMC said to do.
How you do this on your GMC is TOTALLY your business.
Regards,
Rob M.
-----Original Message-----
From: gene barrow
In a recent thread about adjusting front ride height a member stated that he
had been able to make adjustments without the use of a tool to relieve the
pressure on the pork chop. He accomplished this by merely jacking up the
coach and taking the weight off the front wheels.
I would like to read the thread again but I can't find it.
Any one out there remember the post or member who posted it?
Thanks
--
Gene
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Rob Mueller
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
|
|
|
| Re: [GMCnet] Front height adjustment [message #168225 is a reply to message #168223 ] |
Wed, 02 May 2012 00:19 |
captjack
Messages: 159
Registered: February 2010
Location: Sebastopol, California |
Senior Member |
|
|
Jacking it up isn't really enough. You still leave a large load on the pork chop screw. If you unhook the shocks and have the coach jacked up enough to allow the wheel to drop until there is no tension on the torsion bar, you could make adjustments without damaging the bolt, but what a lot of work.
Jack Christensen - K6ROW,
'76 Glenbrook/Clasco - "The Silver Bullet",
'65 Clark Cortez,
Sebastopol, CA
|
|
|
| Re: Front height adjustment [message #168230 is a reply to message #168220 ] |
Wed, 02 May 2012 02:53 |
GMC Cruse
Messages: 337
Registered: June 2009
Location: SE Michigan |
Senior Member |
|
|
| gbarrow wrote on Tue, 01 May 2012 23:08 |
In a recent thread about adjusting front ride height a member stated that he had been able to make adjustments without the use of a tool to relieve the pressure on the pork chop. He accomplished this by merely jacking up the coach and taking the weight off the front wheels.
I would like to read the thread again but I can't find it.
Any one out there remember the post or member who posted it?
Thanks
|
In a post on April 16th, Voodooling wrote:
"Hi I have used a different method to adjust the porkchop bolt.
I take a short bottle jack and put a 1/2 inch X 2 1/2 bolt. You can position it so the bolt sits in the dimple of the porkchop and jack it up to take the weight of most of the pchop. This will take most of the stress off the adjusting bilt and let you adjust as needed.
This works for me without all the tooling needed. The bolt fits between the rear brace and up into the dimple.
Try it you'll like it, Tim "
Mike K.
'75 PB
Southeast Michigan
|
|
|
| Re: [GMCnet] Front height adjustment [message #168236 is a reply to message #168230 ] |
Wed, 02 May 2012 06:30 |
Ken Henderson
Messages: 4165
Registered: March 2004
Location: Americus, GA |
Senior Member |
|
|
When my improperly seated pork chop came off of the torsion bar in Texas a
few years back, I also used a small bottle jack with the plunger swivel
removed to relieve some of the pressure on the adjusting screw. As an
emergency procedure, that worked OK. I do not recommend it as a routine
procedure. The U-bolt compressor works better for me.
Ken H.
In a post on April 16th, Voodooling wrote:
>
> "Hi I have used a different method to adjust the porkchop bolt.
> I take a short bottle jack and put a 1/2 inch X 2 1/2 bolt. You can
> position it so the bolt sits in the dimple of the porkchop and jack it up
> to take the weight of most of the pchop. This will take most of the stress
> off the adjusting bilt and let you adjust as needed.
>
> This works for me without all the tooling needed. The bolt fits between
> the rear brace and up into the dimple.
>
> Try it you'll like it, Tim "
>
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
| Re: [GMCnet] Front height adjustment [message #168245 is a reply to message #168223 ] |
Wed, 02 May 2012 07:31 |
shawnee
Messages: 409
Registered: February 2004
Location: NC |
Senior Member |
|
|
[quote title=Robert Mueller wrote on Tue, 01 May 2012 23:42]Gene,
That is correct; HOWEVER, the Maintenance Manual specifically says not to
screw the bolts in to adjust the ride height.
Reference Maintenance Manual X-7525 Page 3A-20
NOTE: Never attempt to increase the ride height of the vehicle using the
adjusting bolt only, (figure 30). The bolt will turn but will strip the
threads and will necessitate replacement of the bolt. Always use the special
tool.
Now there will be comments that "they" take the weight off the coach and do
it all the time without any problems. I am happy that "they" have been
successful I am merely advising what the guys that designed and built the
GMC said to do.
How you do this on your GMC is TOTALLY your business.
Regards,
Rob M.
-----Original Message-----
From: gene barrow
In a recent thread about adjusting front ride height a member stated that he
had been able to make adjustments without the use of a tool to relieve the
pressure on the pork chop. He accomplished this by merely jacking up the
coach and taking the weight off the front wheels.
I would like to read the thread again but I can't find it.
Any one out there remember the post or member who posted it?
Thanks
--
Gene
quote]
Rob,
Jacking up the front of the coach and then making the pork chop adjustment is the method used in the 1974 maintenance manual. I have done it this way for over 35 years and had no problem. May be a difference in the newer coaches, but they look the same to me.
Gene Dotson
74 Canyonlands
www.bdub.net/Motorhome_Enhancements New Windows and Aluminum Radiators
|
|
|
| Re: Front height adjustment [message #168246 is a reply to message #168220 ] |
Wed, 02 May 2012 07:51 |
lqqkatjon
Messages: 329
Registered: October 2010
Location: St. Cloud, MN |
Senior Member |
|
|
I think the thread was in regards to my question about not wanting to buy the tool for a one time adjustment.
I can see now that the porkchop can be jacked up, to relieve the pressure off the bolt, if someone knows what they are doing and are careful. but the tool would be easier. But what everybody told me, the idea was to jack up on the porkchop, at the same location as the tool would be compressing the porkchop. not just jack up the coach.
I have since looked at my coach, and I have another question:
my passenger side seems to be adjusted down all the way. What is the process now, to lower the ride height? my driver side looks like there is some adjustment. just the passenger side looks like I cannot lower(unscrew) the bolt at all.
again, my front height seems(is) high.
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/
|
|
|
| Re: [GMCnet] Front height adjustment [message #168259 is a reply to message #168223 ] |
Wed, 02 May 2012 08:59 |
gbarrow
Messages: 397
Registered: February 2004
Location: Lake Almanor, Ca. |
Senior Member |
|
|
Rob, Gene, et al,
Thanks for the info.
My front is high. The caution in the manual is against "RAISING" the coach with out the unloader.
Since I don't have a TBar unloader, I'll try Gene Dotson's method to lower the setting. If I need to relieve more pressure I'll use my bottle jack.
Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
|
|
|
| Re: [GMCnet] Front height adjustment [message #168261 is a reply to message #168245 ] |
Wed, 02 May 2012 09:04 |
Robert Mueller
Messages: 9201
Registered: July 2007
Location: Sydney, Australia |
Senior Member |
|
|
Gene,
Thanks for the input.
Wouldn't yah know it as you can see below I got caught out! ;-)
I checked 1973-1974 MM X-7425 Page 3A-20/21 and here's what it "says:"
RIDE HEIGHT
When checking front ride height, the Motor Home parked on a known level
surface, and tire pressure at specified psi.
NOTE: For details on adjusting rear ride height refer to Section 4, REAR
SUSPENSION. If vehicle is equipped with the optional Power Level System, be
sure power level control knobs are set in the "TRAVEL" position prior to
adjusting front ride height.
Measurements must be taken from the oval hole in the frame rail to the floor
(figure 31).
NOTE: Never attempt to increase the ride height of the Motor Home using the
adjusting bolt (figure 30) while the vehicle is on the ground. The bolt will
turn but will strip threads and will necessitate replacement of the bolt.
The procedure to adjust the ride height is as follows:
1. Raise vehicle.
2. To raise the ride height.
a. Clean off adjusting bolt with a wire brush. Apply chassis grease to
threads. NOTE: Failure to use lubricant will strip the threads on the bolt.
b. Turn bolt clockwise.
c. Lower vehicle, check height, turn bolt counter-clockwise to lower if
required.
3. To lower the vehicle.
a. Turn adjusting bolt counter-clockwise as required to obtain proper ride
height
I checked 1975-1976 MM X-7525 Page 3A-20 and here's what it "says:"
RIDE HEIGHT
When checking front ride height, have the vehicle parked on a known level
surface, and tire pressure at specified psi.
NOTE: For details on adjusting rear ride height refer to Section 4, REAR
SUSPENSION. If vehicle is equipped with the optional Power Level System, be
sure power level control knobs are set in the "TRAVEL" position prior to
adjusting front ride height.
Measurements must be taken from the top of oval hole in the frame rail to
the floor (figure 31).
NOTE: Never attempt to increase the ride height of the vehicle using the
adjusting bolt only, (figure 30). The bolt will turn but will strip threads
and will necessitate replacement of the bolt. Always use special tool.
RIDE HEIGHT ADJUSTMENT
NOTE: Tool J-22517-02 (shown in figure 16) must be used the reset ride
height. This tool will raise or lower the torsion bar rear anchor arm so
that the adjusting bolt is not loaded.
1. Install Tool J-22517-02 with pin of tool aligned into hole in
crossmember. Seat center screw in dimple of torsion bar adjusting arm.
2. If vehicle must be raised, turn tool until proper adjustment level is
reached, then turn the adjusting bolt until it makes contact with the
adjusting arm. Remove tool.
3. If vehicle is to be lowered, raise adjusting arm from contact with
adjusting bolt. Lower bolt then lower arm with tool until proper ride height
level is reached. Raise bolt to contact adjustment arm.
Remove tool.
I then went to X-7625 1976 MM Supplement Page 3A-19/20 and the procedure is
the same. The info about the Power Level is replaced by the Electro Level.
Finally I checked X-7725 1977 / 1978 MM Supplement Page 3A-19 and the
procedure is the same.
My guess is that GM mechanics / owners were stripping lots of adjusting
bolts so they revised the manual.
Since you have been doing it using the 1973 - 1974 way without a problem
shows it does work! OBVIOUSLY!
Personally I intend to make two tools that way I can adjust both sides at
the same time with the coach on the ground.
Regards,
Rob M.
-----Original Message-----
From: Gene Dotson
Rob,
Jacking up the front of the coach and then making the pork chop adjustment
is the method used in the 1974 maintenance manual. I have done it this way
for over 35 years and had no problem. May be a difference in the newer
coaches, but they look the same to me.
Gene
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Rob Mueller
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
|
|
|
| Re: [GMCnet] Front height adjustment [message #168263 is a reply to message #168259 ] |
Wed, 02 May 2012 09:15 |
James Hupy
Messages: 2093
Registered: May 2010 |
Senior Member |
|
|
In my experience with GMCs, to find a coach with the front end high is as
scarce as hen's teeth. I am not saying that they do not exist, it is just
that I have yet to discover one that is at the correct ride height in the
rear and front at the same time. The torsion bars are always under some
preload when the upper front shock absorber is still connected, even with
the front suspension completely off the ground. The threads on the
adjustment nut and bolt are not intended to raise or lower front ride
height. That is the purpose of the torsion bar adjustment tool. If you
insist on going against the advise of the service manual, do so with the
knowledge that it may strip the threads on the adjustment nut and bolt. It
is a free country after all, and we are still capable of learning our own
lessons. Remember, that these front suspensions do not arrive at the
correct ride height following adjustment until they have been driven 3 or 4
miles. I have done a lot of ride height adjustments following component
installations and they all exhibit this tendency. JWIHF.
Jim Hupy
Salem, OR
78 GMC Royale 403
On Wed, May 2, 2012 at 6:59 AM, gene barrow <barrowgene@gmail.com> wrote:
>
>
> Rob, Gene, et al,
> Thanks for the info.
>
> My front is high. The caution in the manual is against "RAISING" the coach
> with out the unloader.
>
> Since I don't have a TBar unloader, I'll try Gene Dotson's method to
> lower the setting. If I need to relieve more pressure I'll use my bottle
> jack.
> --
> Gene Barrow
> Lake Almanor, Ca.
> 1976 Palm Beach
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
Goto Forum:
Current Time: Thu Jun 20 00:05:01 CDT 2013
Total time taken to generate the page: 0.02346 seconds |
Search
Help
Register
Login
Home
