Rear suspension

[Jerry Sanders]

Greetings from a new owner.  We purchased our 2000 Marquis last fall and have been chasing minor problems ever since.  The forum has been a wonderful source for me to answer questions abour our rig.  My current problem is with the airbag suspension.  When the coach inflates the bags after it has been parked the driver's side rear is the last to reach full height.  If the coach is left parked with the bags inflated, nothing changes.  The coach does not sag at all.  When we travel down the highway after 30 to 50 miles the left rear of the coach starts to sag and after 100 to 200 miles the sag is substantial and it has once sounded an alarm requiring us to stop and cycle the auto level system and to reinflate the airbags.  I am looking for some help in what direction to take in resolving the problem.

Jerry

[John Hennessey]

We had a similar problem and we replaced the rear solenoid on both sides on the suspension. Also do you have the IDS jacks in addition to air leveling

[Gerald Farris]

The air leveling and hydraulic leveling systems on a 2000 Marquis (if equipped with both systems) are both made by HWH. Most of these models that have the optional air leveling system are also equipped with the OEM hydraulic leveling, and the two systems are combined into one control panel.

I have never had a ride height problem like the one Jerry is referring to, but it is probably related to a height sensor. However, it could be a problem with the air control valve, it is more likely the height sensor. The air leveling system seams like it functions OK from the description, and the air control valves are used by it, but the height sensors are not. The height sensors are only used for ride height.

Gerald    

[Jerry Sanders]

Gerald,  Thanks for the input.  Our coach does have both jacks and air leveling in that combined unit.  I had the coach in the shop today for service on the Allison and to change the engine coolant.  While it was there they tried to trouble shoot the suspension and were unable to recreate my problem.  Driving the coach failed to have the rear sag as we have experienced. Are the ride height units mechanical or electric?  We will just continue using the coach until the problem resurfaces.

Jerry

[John Hennessey]

I can recommend Beaver Coach Sales in Bend. They were able to fix ours I think it ran about $1000 for both put at least our rear suspension stopped sagging

[Gerald Farris]

Jerry,
The height sensors, one at each side in the rear, are electrical sensors that are mechanically linked to the suspension. In most cases, the mechanical linkage is the most troublesome part of the height sensor system.

Gerald

[Jerry Sanders]

Thanks to Gerald and John for the input.  We are due to be back in the Bend area later this year so it looks like a stop at BCS is order.

[Steve Huber Co-Admin]

Gerald,
Do the height sensors activate the appropriate air bags if they sense height needs adjustment? How do they interact with the tricycle air bag adjustors?
Thx, Steve

[Gerald Farris]

Steve,
The height sensors send a signal to the appropriate air controls to either increase or decrease the air pressure in the air bags to maintain the correct ride height.

I am not sure what you mean by the question "How do they interact with the tricycle air bag adjustors?". It sounds like you are calling the height sensors by another name in your question when you refer to "tricycle air bag adjustors".

Gerald

[Adam Hicklin]

Jerry, my air suspension seems to do random one-off types of things.  Now I only tend to worry if it happens several times.  

[Steve Huber Co-Admin]

Gerald,
I was referring to the mechanical adjustors that control air bag inflation. There are 2 on the rear, each controlling the air bag height on their respective sides and on on the front controlling front air bag height. Adjustment is via a hose clamp that sets arm height connected to the respective air valve.
Steve