gene-linda Report post Posted July 10, 2014 I have a 2002 Monaco Diplomat with 100,000 miles. The ride is extremely rough. Coach weighs about 5000# at each front corner and 10000# at rear corners. New Michelin tires, 85# front 95# rear, 40,000 miles on Koni shocks. Air suspension with 2 air bags at each corner and the air gage on the dash reads 115-120# when traveling. I suppose the shocks could be to blame but I suspect it is more than that. Is it possible that the ride could be improved by lowering the pressure in the air bags? If so, how would I go about doing that? genemarshall@comcast.net Share this post Link to post Share on other sites
hermanmullins Report post Posted July 10, 2014 Gene, Welcome to the Forum. This is the way to post a question, with all the fact. If I understand the air ride, which our coach also has, the pressure gauge on your dash give you the reading of the pressure in the air tanks for your brakes and any needed air for your bags. If you lower the pressure in the bags you are in essence lowering the coach. Your air ride suspension, I believe has sensors that keep the bags all at the same pressure and therefore keeping coach level. A call to the Monaco Tech would be the place I would start. They are still in Oregon the last I heard. They are super and will help with your questions. On their web site there is a place you can ask a question and the tech will be back to you in 24 hours or less. Herman Share this post Link to post Share on other sites
dickandlois Report post Posted July 11, 2014 Gene, Welcome to the Forum! The suspensions of coaches designed with air suspension are designed to maintain a specified ride height and travel range. Changing the ride height can cause a number of issues, including drive shaft wear do to angle changes, the handling characteristics, stability and load range and wheel alignment. Plus other factors. Think you could have all the air springs checked for dry rot, as they are about 12 years old. That could have an affect on how the coach rides. That would be a good question to ask the coach builder. Rich. Share this post Link to post Share on other sites
wolfe10 Report post Posted July 11, 2014 Correct. As stated what is adjustable is RIDE HEIGHT. The RIDE HEIGHT VALVES then controls air flow and therefore pressure to the air bags. Monaco can tell you the correct ride height front and rear for your coach. Be sure to use safety stands if you go under the coach. Set too low and the coach can bottom out. Set too high and the shocks act as limiters on suspension travel. Shocks control the up and down motion, not really ride stiffness, particularly with Konis. Share this post Link to post Share on other sites
kaypsmith Report post Posted July 11, 2014 Air bags have limiting valves that are set to determine when the coach reaches the correct ride height. One or more of them could be damaged, broken, or stretched, If any of the above has happened, the ride will be impaired. As Brett said, get the correct ride height, then park the coach on a level hard surface and measure all four corners of the coach to check against the correct ride height. A leaking dump valve on the stationary jacks can cause a ride problem as many other small items can cause it. As Rich said, 12 year old air bags may be a factor, many begin to crack causing a large leak, which the control valve may not be able to recover fast enough. Share this post Link to post Share on other sites
jleamont Report post Posted July 18, 2014 Please let us know what you find, I also have a Roadmaster chassis now. I can only compare to our old class C with springs and air bag helpers, I'm in heaven now with this coach but still very curious what the root cause of your concern is. Share this post Link to post Share on other sites
