RE: [A/S] AutoRide option

["David & Bret" <dtbw_1999@xxxxxxxxx>]

Back in '78-'80, I towed an Overlander with a 1977, 98 Olds Regency with the
electric air shock auto leveler system and a Reese DC.  As has been pointed
out, the system used a sensor mounted between the body and the rear axle to
detect loading.  The system could release air without the ignition switch on
(ie rear end too high), but required the engine to be running to add air (ie
rear end too low).  The system did NOT measure weight on the axle directly
but rather relied on the fact that the distance between the rear axle and
the body changed with different loads.  I believe this is still the way GM
implements auto leveling.

With any equalizing hitch, you want to ensure that the receiver and drawbar
are installed such that the rig can be adjusted allowing BOTH the car and
the trailer to be level and that the hitch height is per Airstream specs.
With that as a given, here is how I hitched up the Airstream and the 98.

First, I allowed the system to properly level the car with the Reese head
installed in the receiver BUT, without the trailer attached.  This properly
inflated the air shocks for the static load.  I then killed the engine and
lowered the hitch jack until it just made good contact with the ball (ie the
actually hitch weight was still supported by the hitch jack and NOT
depressing the rear of the tow car more than an inch).  Then, I would
determine the chain link positions that would just lift the hitch jack off
the ground a fraction of an inch). Of course this meant NOT raising the
hitch and tow car with the hitch jack as it common when pulling the torsion
bar chains over the top (ie I had to use the extension tube to leverage the
chains over the top).  Once I had the chains pulled over the top and locked,
I would then raise the hitch jack which properly loaded the Reese DC.  As a
sanity check, I would eyeball the rig for level front to back as well as
occasionally measuring the hitch height once hooked up.  As long as you do
not raise the rear of the tow car during the hitch processing, the shocks
would not deflate and therefore maintained the proper inflation to handle
the load of the tow vehicle.  Of course without the engine running, the
system would make no attempt to increase the pressure in the shocks and this
allowed me to load the Reese DC properly. 

If you notice that the rear of the tow vehicle RAISES significantly when you
load the Reese DC system equalizing bars so the that hitch height equals the
recommended height (per Airstream), then the Reese head height REQUIRES
adjustment.

As long as you never have the engine running while hitching up AND once you
KNOW the chain link that will result in the proper hitch height, the process
can be shorted...just always use the chain link determined in the above
process, which will always place the same torsion against the hitch and will
result in the same hitch weight transfer and although this may termporarily
result in the rear of the tow vehicle lowering, once the engine is started,
the autolevel will adjust the air shocks to bring the rig up to level. 

Using the method allowed the auto leveler to continue adjusting for changes
in car loading such as filling up with gas or additional rear seat passenger
without conflicting with the Reese DC.  Never had any issues and the DC
worked perfectly using this process as did the auto leveler.

David Tidmore