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Ride Height Issues

I think the ride height on our '03 38ft w/tag is out of specs.  It appears the rear is lower than the front when coach is prepared for travel.  I had FOT change the tag large air springs in Nov '18.  Questions:  1) what is the proper ride height?  2) how does one measure the ride height? 3) is the ride height the same for all axles, ie, is the front different from the rear?  Currently I am parked in a spot where the front is higher than the rear; side to side fairly level.  To level I have to dump the front air bags and add air to the rear bags.  After  about 15 minutes the air leaks out of the rear bags.  FYI - My auto level isn't working, so have to level manually.  Thanks is advance for any info on this subject.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Ride Height Issues

Reply #1
I believe the ride height is 8", there's a great article on Berry's site, beamalarm on the subject.

Until the pros chime in you can read this:

ride-height-adjustment-in-motorhome-or-rv
J.R.
99 U320 40' WTFE
Build # 5388

Re: Ride Height Issues

Reply #2
Don (Don &Tys)  had a great write up that helped me.  I copied and pasted and broke it down by paragraphs before printing:   
"My quick and dirty method to get the ride height adjustment done is as follows;
Edited for clarity (I hope!)
The following is after I had installed new ride height valves, aired up the coach and had already raised the coach and blocked the frame with 12" frame blocks. The ride height valves were already set to neutral position (neither adding or dumping air from the bag). That is the position that the horizontal rod needs to be in when ride height is correct. You have to make sure of the orientation of the valve (they rotate freely 360º) otherwise the valve can add air when it should be dumping or dump when it should be adding. There are marks (hard to see!) cast into the housing to help with this. I did this procedure on a very level flat concrete floor.

First I made two frame blocks out of some 8" long X 1 ¼" pipe nipples, a matching floor flange and a cap that I sawed the top off of to make total height of 8 9/16" (or really close to that). Next, I placed these blocks close to the bags (rear most in the rear and front most in the front). These stands gave me the confidence to be underneath and gave me a firm indication of the spacing between the air bag supporting members. Then I dropped the coach using the HWH control pad to approximate ride height, but just above the supports I made. I then installed the horizontal linkage while already attached to the vertical rods with clamps loose enough to easily move the rubber connecting boots along the vertical and horizontal rods. I tried to keep the ride height valve I was working on in the neutral position while doing this, but the important thing is just not to add too much or lose too much air in the process. You can easily tell when it is dumping or adding air by the sound. The valve is easy to rotate by hand and doing so gives you a sense of how wide the neutral position of the valve is. So as I was doing the adjustment, I would let the coach settle until it touched the stop of my shorty frame block, then rotate the valve the other way until I could see the the weight come off of it. This is where I set the horizontal rod at the 90º position with the vertical rod very close to the vertical. When I could tell that the valve was as close to the middle of its dead zone (zone of not action) as I could make it, I tightened the clamps and checked the links for movement. On the back, it is possible to do the adjustment without being underneath, though in my case, it entailed making an access hatch on the street side compartment I put in.

On the front, it is trickier because you actually have to be underneath while doing the adjustment. That is where I really appreciated knowing that the the lower limit of the coach above would at least be above crushing height if I screwed up or had a sudden loss of pressure. It required several trips between the both sides of the back and then up to the front to get it to where I thought it should be. To test, I dumped all the air (with the engine running and my ride height adjusting frame blocks removed of course!) and let it come back to ride height and check all four corners and then repeated the process by raising the coach to the max and letting it settle back into ride height. The ride height ended up being consistent after doing this, so I called it good.

The trickiest part is definitely setting the front since there is only one ride height control valve up there so you have to split the difference to get an average that gets all corners as close as possible to the correct height. Hopefully, this might help someone trying to do this, but safety first! While I often feel that I would like to be buried in my coach, I have no wish to be buried underneath it! So if you decide to try what I describe above, make sure that you do your own research and understand what is involved. Besides, this was already three months ago so I may have left out a step or glossed over something that could be important to your outcome, so caveat emptor!"
Don
Don
More...
2000 U320 mid entry  #5688
2006 Jeep Liberty


USMCR retired
SDFD retired
FEMA US&R TF8

Re: Ride Height Issues

Reply #3
Thanks for the shout out Sven! Hearing that it was helpful makes it well worth the time it took to write up. Full disclosure: I consider sharing the things I learn about our coaches enlightened self interest, since I could well be the one it helps next time I have to adjust the ride height, since I likely won't remember much by then about doing it the first time! :o Of course, I also learn a lot reading about other's experiences and have saved myself a fair amount of aggravation by following in other's footsteps. Viva la forum!
Don
Don (Don &Tys)  had a great write up that helped me.
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Ride Height Issues

Reply #4
Hey Don,
  I just read a little of your write up. In it you say you take measurements from the bags at the rear of both axles. I had a conversation a few years back with HWH about a problem and I am pretty sure they said you measure from the front bags on the rear axle. Was that a mistake on your part or theirs? Do you know?

Mark
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Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara

Re: Ride Height Issues

Reply #5
Mark,
I couldn't find where I said to take the measurement on the rear set of bags on both axles, but I used the info in a quote attributed to James Trianna. Here is a post in which I quoted James T's statement (in bold here) with a link to Beamalarm on ride height adjustment;
Here is a handy thread on the summary from Beamalarm.com on the subject of ride height adjustment;
ride-height-adjustment-in-motorhome-or-rv
I think the simplest place to measure it is between the frame members next to the air bags. The distance there is ideally 8 ½", or 8" between the air bag mounting plates since the mounting plates are ¼" thick. A template made in the shape of a "C" makes it easy to hold against the air bag and measure the span from the top of the top plate to the bottom of the bottom plate. Or, simply cut a stick or piece of pipe to 8 ½" and fit it next to the air bag. Since there are only three height control valves, two in the back and one in the front, there will likely be some averaging involved in the front measurements. I found this quote attributed to James Trianna, "According to James Trianna the anchored rod should be vertical when the coach is in travel mode and the air spring measures 8.5" from the top of the top plate to the bottom of the bottom plate. The anchored rod vertical adjustment is achieved by repositioning the control lever in or out. Additionally,  measurements should be taken at the bags behind the front wheel and in front of the rear wheels."
I just went through this when I changed out all three ride height valves at Bill C's warehouse and I did go through several evolutions with the adjustment. Essentially, setting the height of the front as close as I could come to having both side in the ball park, and then doing the back one side at a time, then redoing the front. rinse and repeat a couple of times. Then dumping the air completely and raising it completely and then letting it settle to ride height each time. I was able to get the backs almost dead on consistently, and after several tries the fronts were within a quarter inch of the desired measurement or within a half inch of each other. Since this was my first time doing this, it took a couple of tries to get the feel of it. I am sure next time will go a bit quicker.
Don
However, it is entirely possible that misstated it somewhere else... sorry if that is the case.
Don
Hey Don,
  I just read a little of your write up. In it you say you take measurements from the bags at the rear of both axles. I had a conversation a few years back with HWH about a problem and I am pretty sure they said you measure from the front bags on the rear axle. Was that a mistake on your part or theirs? Do you know?

Mark
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Ride Height Issues

Reply #6
Can't put my hands on  the documentation, but ride height is measured at the bags toward the CENTER of the coach.  So rear of the front and front of the rear.

Someone with Motorcade membership may want to confirm this with James Triana.  THANKS.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Ride Height Issues

Reply #7
Thanks for the clarification guys. It was here on Beamalarm site that I read it.
ride-height-adjustment-in-motorhome-or-rv
I thought it was written by Don. I was wrong, sorry. It is in the paragraph before the first picture. Thanks again.

Mark
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Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara