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Re: Quad bag height adjustment

BH
Bruce Hislop
Fri, Jul 8, 2022 1:15 PM

I seem to be getting double messages posted on the web version lately, one from web forum and one through the email system.  So I'll pick this one to
answer on.

You have a '77 Palm beach like mine, so you should have ElectroLevel I with electric switch height controls on the left side.  With the center switch
on Hold position, you can use the Driver & Passenger switches to manually raise and lower the rear suspension.  When you return those switches to the
center position, it will hold at the current pressure and height.  With the center switch in the Travel position, the rear suspension ride height
(pressure) will be controlled by the Ride Height Control Valves in the wheel wells.

So you set the Ride Height Control Valves to the proper ride height for traveling down the road.  I like to use Travel position for the first minute
or so once I am on the road to set the height, then I switch to Hold mode.  When you come to your driveway, set the center switch to HOLD then use the
Raise position of the two outside switches to increase the rear pressure (height) to get in your driveway. Once you raise the rear, moving the
switches back to the center position will maintain that ride height.  When you leave your driveway, move the center switch to Travel and the coach
will assume the proper ride height based on the rear height control valve settings.

You will find the coach runs down the road better if the rear is slightly lower than the front when set to the proper ride height.  The measurements
are in the Service Manual.  There are several theories for this, but mine is that with the bogie pins set slightly below the center of the rear
wheels, the bogies will be sitting in a more directionally stable position (think of lying in a hammock).  If you increase the ride height to make the
coach more "Level" front to back, then the bogie pins will be above the center of the rear wheels and the bogies become less directionally stable and
the rear will start to steer a bit.

Just my farmboy mechanic way of seeing things.

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that

I seem to be getting double messages posted on the web version lately, one from web forum and one through the email system. So I'll pick this one to answer on. You have a '77 Palm beach like mine, so you should have ElectroLevel I with electric switch height controls on the left side. With the center switch on Hold position, you can use the Driver & Passenger switches to manually raise and lower the rear suspension. When you return those switches to the center position, it will hold at the current pressure and height. With the center switch in the Travel position, the rear suspension ride height (pressure) will be controlled by the Ride Height Control Valves in the wheel wells. So you set the Ride Height Control Valves to the proper ride height for traveling down the road. I like to use Travel position for the first minute or so once I am on the road to set the height, then I switch to Hold mode. When you come to your driveway, set the center switch to HOLD then use the Raise position of the two outside switches to increase the rear pressure (height) to get in your driveway. Once you raise the rear, moving the switches back to the center position will maintain that ride height. When you leave your driveway, move the center switch to Travel and the coach will assume the proper ride height based on the rear height control valve settings. You will find the coach runs down the road better if the rear is slightly lower than the front when set to the proper ride height. The measurements are in the Service Manual. There are several theories for this, but mine is that with the bogie pins set slightly below the center of the rear wheels, the bogies will be sitting in a more directionally stable position (think of lying in a hammock). If you increase the ride height to make the coach more "Level" front to back, then the bogie pins will be above the center of the rear wheels and the bogies become less directionally stable and the rear will start to steer a bit. Just my farmboy mechanic way of seeing things. -- Bruce Hislop ON Canada 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001 My Staff says I never listen to them, or something like that