Community Forums

krob911 · 07-27-2018, 06:57 PM

I noticed today that my RV was leaning to the driver side. I checked dimensions from the top of the fender well down on all four corners and yes the left front corner was down 2 inches. I tried to adjust the airbags that level the coach and was unable to get it any closer than an inch and a half difference. When I let the coach all the way down without any air in it bags there still an inch and a half difference between the left front and the right front corner. It leads me to believe that my frame must be twisted somehow. I adjusted the airbag height per the instructions of the mfg. any ideas or is this not an issue?

Old Scout · 07-28-2018, 05:48 AM

….I have spent a fair amount of time "worrying" about this issue too. Measuring from the belt line trim to the ground, my 2003 is between 1 and 1 1/2 inches different, side to side, in front--bags up or down. Still can't explain the difference but in the process, I started looking at the relationship between bag height and 4-corner weight distribution. The first thing I learned is that the specs. of 7 1/2" in back and 10 5/8" in front[or something like that] is difficult to measure precisely. Second, you can transfer significant amounts of weight [especially cross-corner] with very little adjustment to height. Running repeatedly thru the scales at the local truck stop, I was able to isolate all 4 corners and after several iterations, was able to get rear axle "balanced" to within in 500lbs and front axle within 250lbs[normal travel load and me outside[smile][rear axle was almost 1800lbs different when I started and was still within height specs].

Bottom-line: Not sure my assumptions that axle weight should be balanced or that coach should have perfect stance -- no lean. However, along with new hardpan [track] bars front and back, my 2003 [with 175k miles] drives better than ever, perhaps better than when I bought it! I should also note that early on in ownership, I was fighting excessive front tire wear [similar to river-ing]. In all fairness--had this issue with Toyo and Good Year tires--now on my second set of Bridgestone with no excessive wear patterns....

wolfe10 · 07-28-2018, 07:04 AM

This is for the 2003, but very likely applies to other years as well:

Alignment Specs: at spec ride height

Front ride height: bottom of frame rail to top of axle 10 5/16”.

Rear ride height: bottom of frame rail to midline weld seam of rear axle 7 ½”.

A 1' ruler and a 6" "L" or straight edge to extend the line of the top of the front axle so you can measure vertically work very well.

I found I needed adjustable links to achieve correct ride height on our coach-- very easy to get it exact:

https://www.heightcontrolvalve.com/shopexd.asp?id=109

Old Scout · 07-28-2018, 07:32 AM

….Brett, no offense intended but IMHO, the word "exact" doesn't really apply here. My experience is that the ride height tends to vary every time you stop. Add in changing weight/load distribution and you have yet a another variable. I feel pretty comfortable that I have "mastered" the art and science of ride height vs 4-corner weight distribution. But I still scratch my head as to why the coach tends to lean to one side or the other, or that the front end seems to ride considerably higher than the rear--perhaps by design--but looks like I am always going uphill???

wolfe10 · 07-28-2018, 09:37 AM

When I first tried to adjust ride height (before going to the adjustable links) I ran into the same thing. And before any adjustment, mine was more than 1" too high in front.

But after dialing it in I was consistently able to have it withing 1/4" of spec on all corners. Measured it in the same concrete pad in our storage barn each time I did a LOF. With coach aired up and jacks stowed, only adds 5 minutes to the LOF.

Old Scout · 07-28-2018, 01:46 PM

….in light of your precise leveling outcome, I would be curious to hear what your 4-corner weight distribution is? May have to re-think my whole theory on this issue...again [smile]

wolfe10 · 07-28-2018, 01:58 PM

Did not have a 4 corner weight done after the adjustable links/ride height adjustments made.

But, left to right weight distribution is very dependent on floor plan. With galley slides being the having the most left/right imbalance.

Old Scout · 07-29-2018, 07:16 AM

...again, back to my theory--I spent the afternoon at the truck stop scales adjusting my bag height until I was able to achieve near balance on left to right weights at the corners--less than 500 on rear; less than 250 on front. I agree 4-corner weight is dependent on floor plan but the question is how much??? My coach is still within height specs [perhaps not "exactly"] and weight is well balanced side to side--so the question is: "is this a good or a bad thing?"

wolfe10 · 07-29-2018, 08:46 AM

Quote:

Originally Posted by Old Scout

My coach is still within height specs [perhaps not "exactly"] and weight is well balanced side to side--so the question is: "is this a good or a bad thing?"

Excellent question-- and certainly open to speculation.

I would certainly not hesitate to raise the "light" side 1/8" and lower the "heavy" side 1/8". 1/4" +/- maybe. More-- don't think so.

RVPioneer · 07-29-2018, 10:39 AM

Quote:

Originally Posted by Old Scout

My coach is still within height specs [perhaps not "exactly"] and weight is well balanced side to side--so the question is: "is this a good or a bad thing?"

At the grave risk of answering a potentially rhetorical question, the obvious answer would seem to be that a coach set up within ride height specs and well balanced would be a good thing.

However, these days, comparing good to bad may be perceived as judgemental and divisive. We wouldn't want to lower our coaches self esteem by making it feel inadequate. They can be sensitive about those things.

Of course it's only a matter of time until someone comes up with a completely plausible explanation as to why your coach is set up incorrectly.

Pollo man · 07-29-2018, 10:41 AM

While on the subject of air bags
What is the correct Bag/spring air pressure going into the bags MIN/MAX?
Neway book states the Air pressure protection valve & filter is set at 70lbs for safe air brake pressure.
Anyone ever checked the pressure?

Since we do not have air brakes could this pressure be changed to soften the ride?
Or if the valve fails could this stiffen the ride?

wolfe10 · 07-29-2018, 11:07 AM

Pollo man,

Ride height and coach weight control bag PSI. If you have less PSI to a corner/air bag, that corner would sit lower than spec.

No reason to check PSI that I am aware of.

The ride height valves control how much air (and therefore PSI) goes to each bag to achieve ride height.

krob911 · 07-29-2018, 01:15 PM

Quote:

Originally Posted by krob911

I noticed today that my RV was leaning to the driver side. I checked dimensions from the top of the fender well down on all four corners and yes the left front corner was down 2 inches. I tried to adjust the airbags that level the coach and was unable to get it any closer than an inch and a half difference. When I let the coach all the way down without any air in it bags there still an inch and a half difference between the left front and the right front corner. It leads me to believe that my frame must be twisted somehow. I adjusted the airbag height per the instructions of the mfg. any ideas or is this not an issue?

Thank you all for the answers. An additional delima is I dumped the air and leveled the coach with the jacks and my left front corner is stil 1.75 lower the the other corners. Baffeling I’m thinking I must have a manufacturing issue. And yes when I put the bags at the correct ride height I can not install the fixed linkage. Consequently I will be ordering the adjustable linkage for all 4 corners.
I’m to the point the coach rides and drives nice, but I wonder how much nicer it could ride? I am the second owner of the coach with only 50k miles and has been very well care for so I don’t think wear is an issue.

wolfe10 · 07-29-2018, 02:40 PM

Quote:

Originally Posted by krob911

Thank you all for the answers. An additional delima is I dumped the air and leveled the coach with the jacks and my left front corner is stil 1.75 lower the the other corners.

Consequently I will be ordering the adjustable linkage for all 4 corners.

Two unrelated issues. The first probably just involves calibrating the HWH level sensor. And easy job with a screw driver-- it is in the HWH manual and on their website.

As I recall, I needed two different "length ranges" of adjustable links. Measure yours and determine which ones work where. But, boy do they make ride height adjustment easy.