I noticed the last couple trips the coach seemed to ride differently. I found the ride height was 8" on the front and 7" on the rear measured at the airbags. The coach is level side to side. What would cause the rear of the coach to ride at 7" instead of 8" and how do I correct it. Thanks in advance for your help.
You have two ride height valves in back, one in front. Odd that both rears would "drop" an inch at the same time.
But, bottom line, you need to adjust. That inch doesn't seem like much, but to that 18" driveshaft, it is a LOT!
Hi Brett, I agree it seems odd the rear would drop 1" on both corners at the same time. I was initially thinking the front height changed since there is only 1 adjuster up front and side to side was still level but the front ride height is 8" and the rear 7". So I guess my question is should I adjust the ride height on both rear wheels to get back to 8" on all 4 corners using the rods at each rear wheel.
Was just at FOT and was told ride hight should be 8.5" measured plate to plate at the air bags. If you are going to do it might as well hit factory specs. :)
see ya
ken
Hi Ken, 8 1/2" from the top of the upper mounting plate to the bottom of the lower mounting plate correct? which would still be 8" measuring from the bottom of the upper mounting plate to the top of the lower mounting plate because each plate is 1/4" thick.
Angle finder on the trailing arms also works.
Now you're making me dig deep in the memory. I'm pretty sure it was from the bottom of the top plate to the bottom of the lower plate. The lower plate is a little deceiving. There are 2 plates on the bottom. There is a plate attached to the bottom of the air bag and one attached to the coach. You should see a seam between them. Measure to the seam. At least it's that way on mine.
see ya
ken
Thanks for the clarification Ken. I would still like to understand what caused this condition to happen. How both rear corners could drop an equal amount when there is a ride height valve on each corner. It just doesn't make sense to me.
I was wanting to know the answer to this question also.
Found this old thread ... As explained by Brett it's the space occupied by the air bag assembly. Should be 8"?
Ride height measurement-which points? (http://www.foreforums.com/index.php?topic=12419.0)
Are you sure the ride height wasn't at 7" before you noticed the change?
It would make more sense the single front adjustment may have slipped a little.
In my case I have had both the air bags and the shocks replaced at separate times. Could have disconnected the adjusters at either time. I suspect (wild-ass speculation on my part) that it was when the shocks were replaced. FOT did the bags and they know what the ride height should be. Bob Ireland (FOT service tech) showed me a piece of aluminum that was cut out in a C shape with the opening exactly 8.5". Made it easy to check by just holding it next to the air bags.
see ya
ken
That link is no longer working
Maybe try it again. It works for me.
Chris
The link works to the thread but the link with the measurement doesn't at least for me.
@craneman,
Try this one. (the beamalarm site changed over from htm extension to html)
ride-height-adjustment-in-motorhome-or-rv (http://www.beamalarm.com/Documents/ride-height-adjustment.html)
The article contradicts what Bob Ireland said. It claims air bags should be 8" + or - 1/4". Take your pick... :)
see ya
ken
Hi Fourtravelers, It does make more sense that something happened at the front of the coach. I do know the coach road level before, What I don't know is what the front and rear ride height was before I noticed it was not level. It could be the coach was 7" front and rear and something caused the front to raise. The bottom line is the coach is not level and needs to be level front and rear at 8" so I will make that happen. Now to find a nice level spot to make the adjustments. I purchased the coach last October and I am very happy with it. This Forum has been very helpful and has added to my enjoyment of the coach.
Where do I find the specs for the angle on the trailing arms. I have one for the race car and that might be easier and more accurate.
On my 91 under the dash on the passenger side is a tag with the toe in,caster,camber ,ride height,etc.
Adjusted the ride height this afternoon (after replacing all 8 airbags) rear was 9" and front was 8-3/4".
Set the rear at 8" and left the front at 8-3/4". I liked the little extra clearance on the front, maybe tires won't rub as easily on driveways. Dunno'
Don't think 3/4 " will affect anything, no driveshaft to be concerned with as in the rear.
After reading about ride hight this morning, I measured my front and back ride hight and had 8" on all but the left rear which was 7". I took it in to a shop and they found that the left rear leveling valve adjusting rod bracket was bent and the bushing was broken. They made a new bracket and replaced the bushing and all is good again.
Thanks to the Forum I found I had a problem, learned something and got it fixed.
If it helps, and I hope not misleading, I had the front end aligned and ride height set.
A month later, for other reason, I had Keith Risch at MOT drive the coach. He is a quiet fellow, not full of fanfare, and all I found related to this discussion (the purpose of the drive was another matter) was a note on a napkin left in the driver's seat, "I found the ride height off, it will ride like a Foretravel now."
I had not known Keith then as now, but at that time I search the shop, found out who he was, asked him what was this about. He said the height was 1/4 inch off and it makes a difference.
Perhaps some will disagree that small amount is that critical but I offer it to help you consider how you make the measurements and what you think is or is not important, might verify with expert opinions if any doubts the answers.
I did also notice I was having to make slight steering corrections almost constantly on my last drive of about 200 miles. Hopefully when the ride height is corrected it will drive better too.
Our coach needed the front suspension components resealed up as the rubber parts were gone.
As there no play in the Pittman arm or drag link ends on ours the next step was to put a slight preload on the front wheel bearings.
No dead spot.
Well I finally found a nice level spot to explore my ride height issue. I found the front lower bracket for the adjusting arm had twisted and that seems to be why the front ride height changed (increased). Apparently the coach ride height had been at 7" all around prior to this. I realigned the front lower bracket which resulted in the coach riding at 7" again front and rear. I then adjusted all 3 ride height control rods and am now at 8" all around. The steering wonder is gone also so ride height can effect steering. Slowly working my way toward the Alaska Highway again.