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Discussion Starter #1
trying to improve the ride and handling of our super c motorhome on the C5500 chassis. so far I've installed Koni fsd shocks, firestone air helper springs, davis tru-trac front trac bar, hellwig front sway bar, ultratrac rear trac bar, and upgraded/uprated from the G rated 225 series tires to H rated 245 series tires. the handling has improved quite a lot however the rear end ride is still horrendous at best. unfortunately air ride is not an option 1) due to cost and 2) the systems that are available are not rated for the weight on the rear axle so I'm basically stuck with the leaf springs. had a spring shop local to me take a look and he recommended switching the rear tapered leafs out to traditional multi-leaf style. however i was quoted $3500 installed for this :eek: i contacted Deaver and they recommend staying with the taper springs and adding an additional leaf to each pack as GM used to offer as an option to up-rate the springs for heavy loads such as my situation so that i can run a lot less pressure in the air bags. this option is far more reasonable cost wise however ill have to figure out how to do this job myself.

thoughts? suggestions? am i wasting my time trying to get a better ride out of this old covered wagon?
 

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Whats the thought behind the trac bar? Does it wonder?
 

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How much air do you need in the helper air springs?
 

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Discussion Starter #5
Whats the thought behind the trac bar? Does it wonder?
It did quite badly and the trac bars have reduced it significantly. A lot of this has to do with the ridiculous overhang behind the rear axle. Thor really should have used the longer wheelbase that was available.

Have you considered SuperSprings?
I have but am not sure if I'll be able to retain the air helper springs? Anyone know?

How much air do you need in the helper air springs?
Currently approx 100 psi for the best ride and to keep the rear from sagging which is max they are rated for.
 

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Discussion Starter #7
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Have you weighed your rig fully loaded? My guess is your front axle does not have enough weight on it.
 

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Discussion Starter #9 (Edited)
Have you weighed your rig fully loaded? My guess is your front axle does not have enough weight on it.
You are correct, Ron. I've scaled it only once so far. towing my jeep on my old 18ft big tex all steel flatbed trailer (I've since downsized that to a 16' wood deck flatbed), about 30 gallons of water in the fresh tank, full propane, 3/4 tank fuel, the usual stuff for an extended weekend in the Eastern Sierras came in as follows...

steer axle: 4,560lbs
drive axle: 15,380lbs
trailer axle: 5,500lbs
total axle: 25,440lbs

the front axle is way too light and the drive axle is way too heavy. i have moved basically everything of any weight to be in front of the rear axle. only camp chairs, small bbq grille, small folding table, etc are in the rear compartments. i almost never travel with anything in the holding tanks (which are behind the axle), the fresh water tank is in front of the axle, the generator is in front of that, batteries in front of that. i cannot do anything about the 80 gallon diesel fuel tank and 24.5 gallon propane tank that are behind the axle obviously. Thor really missed the mark on choosing the correct wheel base chassis for this floor plan. the final floor plan above mine is only about 10" longer overall length but has the longer wheel base and from what i can find, does not have the weight distribution issue that my floor plan does.
 
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This is over the top but do you think you could move the rear axle back? The other option is to get a different unit. Sounds like the issue has been identified for sure.



Maybe one of these?
 
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Discussion Starter #11
This is over the top but do you think you could move the rear axle back? The other option is to get a different unit. Sounds like the issue has been identified for sure.

Maybe one of these?
Everything from the fuel tank, propane tank, holding tanks, services bay and the whole bathroom would have to be reworked to move the axle back. I'll be getting a different unit before trying that nightmare.

Tongue weight isn't really an issue as it's only around 600lbs and the motorhome rides and drives the same whether the trailer is attached or not.

Even thought about building a tray behind the front bumper to put tractor weights into to get some more weight on the front axle....
 

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My Endura 6340 had similar overhang and position of utilities. Wheel base was 239.5". Just looking at your pictures. I see your fridge is on driver side in the slide. Mine was on passenger side. Propane was under driver side slide.
Weight's were done fully loaded.
Front 6,500
Rear 15,000
Car 4,000
With the kitchen in the slide you may have more weight on driver side than mine did.
I had a 4 corner weigh done in 2007. Side to side weights were within 100 lbs.
Wish I could recommend something to help. Maybe equalizer hitch for trailer. But I am not sure frame extension will take the load.
 
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Discussion Starter #13
My Endura 6340 had similar overhang and position of utilities. Wheel base was 239.5". Just looking at your pictures. I see your fridge is on driver side in the slide. Mine was on passenger side. Propane was under driver side slide.
Weight's were done fully loaded.
Front 6,500
Rear 15,000
Car 4,000
With the kitchen in the slide you may have more weight on driver side than mine did.
I had a 4 corner weigh done in 2007. Side to side weights were within 100 lbs.
Wish I could recommend something to help. Maybe equalizer hitch for trailer. But I am not sure frame extension will take the load.
The model is the 34G (side hall hence the 2 big windows you see above the rear wheel). The front slide has only the fridge and the dinette in it. The kitchen is an L shape with the sink on the right side wall just behind the side door with the range and microwave in the middle of the floor. Standing in front of them you are facing the rear of the coach. The generator is under the front slide and the propane tank is on the right side just behind the rear wheels.

Has the 213.5" wheelbase. The other model I was referring to is the 35B which has the 239" wheelbase, same as yours was.
 

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Discussion Starter #15
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I installed super springs on my 5500 and that lifted the rear end up some and transferred some weight to the front.
Also I tow a 24 foot enclosed trailed and I weighed it with and without weight distribution hitch. with the distribution hitch I saw about 300 lbs transferred to the front axle. I really don't need the distribution hitch but the motorhome does drive better with it on. Might be something to look at.
 

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Discussion Starter #17
I installed super springs on my 5500 and that lifted the rear end up some and transferred some weight to the front.
Also I tow a 24 foot enclosed trailed and I weighed it with and without weight distribution hitch. with the distribution hitch I saw about 300 lbs transferred to the front axle. I really don't need the distribution hitch but the motorhome does drive better with it on. Might be something to look at.
the additional leafs showed up from Deaver today and will get installed on saturday. that should be an interesting job given the size and weight of everything. I'm a mechanic for a living but what i work on (german cars) are a whole lot smaller!

i was looking into a distribution setup but the issue is the long ass on the moho already drags the hitch all over the place as it is. i run a 6" drop ball mount for my trailer to be level and the nut on the bottom of the ball is pretty trashed after only 8 months :eek: i can only imagine what'll happen to the poor spring bars
 

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Should try a Kelderman Air Suspension set up, I am installing it on a C5500 4x4 and the kit is great quality and well built, I am very impressed can't wait to try it on our terrible roads here I used a 4 bag system for the back axle and a 2 bag in the front, a level valve for every side.
 

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Discussion Starter #19 (Edited)
got the springs installed today. nothing very complicated but since everything is quite large it just made it a loooong day. after much thought, i removed a couple of the small stacked leaf block spacer things to compensate for the additional leaf spring in pack height and am glad i did. measurements taken at the rear wheel opening showed that the ride height has increased only about 3/8" with the springs installed and no air in the helper bags compared to what it was before with about 100psi in the air bags. I'm only running them with the minimum 5psi now. the overall ride doesn't seem much different, slightly less bouncy but the biggest change I notice is that the rig is much more stable on the road and doesn't seem so top heavy now.

I'm done with it now, I've spent enough time and $$ on this. next step is either going back to a 5th wheel or stepping up to a diesel pusher.

Should try a Kelderman Air Suspension set up, I am installing it on a C5500 4x4 and the kit is great quality and well built, I am very impressed can't wait to try it on our terrible roads here I used a 4 bag system for the back axle and a 2 bag in the front, a level valve for every side.
thats a pretty serious setup right there, wow! seeing it on their website is one thing, seeing it actually in place on a chassis like this is way more impressive.
 
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