rbreak
Fl
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Hello all,
I recently bought a 2008 Winnebago Access 29t class C with the Ford E-450 chassis. The suspension appears to be all stock with only 21k miles on the coach. It handles acceptably concerning wind or semis passing by, turning is ok and it’s not wandering all over the road or driving poorly in those areas. Where it’s not so good is bumpy roads, rail road crossings, expansion joints, etc. It is jarring, slamming and extremely harsh in that area. I do understand that this is a 12K+ lb big truck with a heavy duty suspension, I owned a Dodge Ram 2500 4x4 quad cab diesel for almost 9 years so I get that heavy duty trucks are not going to ride soft, and I’m not expecting it to ride like an suv or anything, I was just wondering if there is any proven improvement to the slamming and jarring over the bumps. It sounds like it’s going to break something on some of the bumpier roads, I don’t know if it’s bottoming out or the suspension is so stiff in the back that its hardly even absorbing anything. I have done some searching and reading on here and read about the Koni FSD or Bilstien shocks, but I was wondering if some of the other suspension options like sumo springs, timbrens, air bags, etc. help any with the slamming. I did a lot of searching and could not find much info on those items concerning smoothing out the ride. My rig already has fairly thick front and rear sway bars, and I’m not sure how putting in a bigger, stiffer sway bar would help on the bumps, so I hadn’t really considered that. I have also read up on the tire pressure for actual weight and will experiment with that as soon as I can get the coach weighed on a cat scale.
Thanks in advance for any help, ideas, experience or information. If there really isn’t a reasonable way to improve the ride, that is ok too but I don’t want to be miss it if there is a readily available improvement.
(On a separate note, I had to post this using Woodall’s forum, could not get picky rvnet to accept anything)
2008 Winnebago Access 29T
Class C w/Ford Chassis
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DrewE
Vermont
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Joined: 08/23/2014
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It's hard to offer good suggestions without really understanding what's going on. Probably a good truck spring and chassis shop could give you a better opinion than I have any hope of doing (and, for that matter, that would still be very much true even with my examining the rig in question). However, it does sort of sound like you're hitting the bump stops, in which case stronger springs and/or air helper springs or similar aids should improve things. It's not out of the question that you may have a broken or worn out spring, too.
I do have ride-rite air helper springs on my class C. They do make a noticeable difference (improvement) in its composure in going over bumps. It's not a miraculous change, but it is enough that I'm happy to have them. If nothing else, they do help keep the ride height at a reasonable level (and so give more possible suspension travel when needed).
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Healeyman
Carrollton, TX
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Joined: 09/08/2006
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Rob,
Our first RV was a 22' Four Winds on a Chevy 3500 (1 Ton) truck chassis.
When we first got it, the ride was like yours, TERRIBLE!!! We actually had silverware bounce out of the drawer and broke glassware in the cabinet.
One day, I crawled underneath and looked at the spring stack on the rear axle.
The 13 leaves of the spring stack were absolutely FLAT. There was NO arch in the springs. When striking a bump, the rear axle could NOT move UP to absorb the blow.
The air in the rear tires was the ONLY suspension that there was. The axle housing was still 2 inches from the rubber bump stops (POOR design).
I ordered a set of 5,000 lb. capacity Air-Lift air bags (about $200) and installed them myself in a couple of hours. I didn't even have to jack up the body to get them installed. I ran the air inlet tubes to a storage bay.
When I added 55 pounds of air (about 1/2 full) the body actually rose up 1-1/2 inches. Now I had 1-1/2 inches of Tire, spring, and air bag travel.
The bags made it an ENTIRELY new RV. It was wonderful!
Later on, I added Bilstein shocks to the FRONT in order to stabilize and eliminate the "porpoising" on that end.
In the end, the ride was FANTACTIC!!! The ride was almost as good as that of my 3-seat GMC Suburban.
When we upgaded to a 28 ft. Coachmen Freelander, it came with Air-Lift air bags installed at the factory. I have never had to add air to them to use them.
I suggest that you or a shop-guy look at the rear spring stack to see whether or not you have any, or adequate, rear axle UP-travel.
Tim
![[image]](http://i1084.photobucket.com/albums/j404/healeyman/Rig1.jpg)
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tpi
Southern CA.
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Joined: 02/22/2005
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First thing I'd do is have the motorhome weighed and then use tire weight/pressure chart to set the tire pressure based on the weight on the tire.
This usually winds up being more productive in the front, and some people go around with 20 plus PSI extra in front over need. Carrying excessive pressure will hurt the ride.
Otherwise, I don't know. I have the FSD shocks. I think they may have taken a bit of harshness out, but there is still some. Another poster here thinks they made a great improvement. I think the basic E450 rear leaf suspension has quite a bit of friction that transmits harshness. Perhaps some tires are better in this regard than others. Maybe very old tires have excessive stiffness.
I find my ride tolerable and quite good on good roads. On bad bumps it can be harsh, I slow down and get through it.
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klutchdust
Orange, California
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Joined: 06/09/2004
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I don't know how to do links but this is what I did .
> Koni FSD shocks installed (updates)
do a search on this forum and see if it could help you, it sure did change my ride dramatically...
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Bordercollie
Garden Grove, CA, USA
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Joined: 03/07/2002
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Our 2004 Tioga 27 foot 26Q has harsh ride on concrete highways that are cupped from big rig and weather wear. The ride is acceptable on smooth asphalt roads that are in good condition. The left lane on a 2 lane asphalt road is usually the smoothest but faster car and semi traffic gets on your tail so you have to go to the right lane if you want to drive at 55-65 mph. Some have suggested taking out one leaf of the rear springs to get less stiff suspension which may work on some rigs. I added rear air bags to our old 79 Delta 23 footer, it didn't help harsh ride. I recommend frequent rest stops to let your brain stop rattling. Tires seem to fail on hot days with pounding road surface.
* This post was
edited 05/24/16 08:15am by Bordercollie *
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samven1
Hedgesville, WV usa
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Joined: 07/17/2003
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I would have the front and rear sway bars checked to see if they are aftermarket. Someone may have been trying to improve the handling and beefed these up too much. You will get a stiffer more harsh ride with heavy sway bars but thats the trade off. Since you already have experience with a 2500 pickup you know that a heavy truck rides smoother when loaded close to its rating and the E450 has some pretty beefy springs. If you get it weighed the way you plan to travel and its light in the back you can have airbags installed and have a leaf or 2 removed, if you are near or over the limit or the springs are weak from sitting loaded and the last leaf is doing any work airbags will lift the rear a bit and give you a cushion. Many times that last leaf is an overload protector and is very very stiff. A good truck suspension shop could tell you what it needs but it must be loaded the way you travel when you take it in.
Sam
03 Dodge Ram 1500 QC LB Hemi
2015 Four Winds 22E Chevy
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rbreak
Fl
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Thanks everyone for the replies. I have crawled under the coach to look around, the leaf spring is an 11 leaf pack if I remember right, and they were pretty much flat if not a little inverted, I just figured that was how they were supposed to be. Maybe they are sacked out, I know this coach sat a lot to be 8 years old and only have 21k miles on it. I remember there was what seemed like a reasonable amount of space between the rubber bumpers but maybe there should be more. Nothing looked cracked or broken that I could see, and by my measurements with a set of calipers the sway bars are smaller than the aftermarket bars offered by hellwig so I assumed they were stock ford parts. I'm a little skeptical of the expensive brand name shocks because I tried the bilstein's on the dodge ram 2500 pickup I had and to be honest, I was disappointed, I couldn't tell much difference from the stock ones I took off. But I might give the Koni's a try one day. I see a lot of folks seem impressed just changing to the monroe rv shocks at about a quarter of the price of the koni's. It sounds like the airbags might be the best bet to gamble on, I was hoping someone had used the timbrens or sumo springs with good luck as I wouldn't have to worry about an air leak.
Thanks again for all the great info and experiences. I do appreciate it.
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rockhillmanor
On the Road
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Joined: 12/06/2003
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Quote:It is jarring, slamming and extremely harsh in that area
Leaf Springs
Leaf springs fatigue and/or can break. You won't always be able to see that either. And there is also a rubber type grommet that fails and/or moves.
Take it to a frame shop. They have the knowledge and equipment to calculate what should be on the coach and if there is a problem with existing equipment. Stay away from RV shops they don't know squat. The frame shop is also very affordably priced.
Mine was slamming also. Took it to a frame shop. They added a leaf. Rides like a limo now.
And for the front? What are you running on the front tires? I have less air in the front tires than on the duals. That is what most of us do to help the stiff ride and get better tire to ground for better handling.
We must be willing to get rid of the life we've planned,
so as to have the life that is waiting for us.
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samven1
Hedgesville, WV usa
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I agree with rockhillmanor, if your spring packs are flat you really need to get them checked and the RV weighed. With my 24' on a 3500 chassis and a 300 lb motorcycle on a hitch carrier my springs are no where near flat. I did put airbags on mine but not because the springs flattened, I just wanted a little more cushion for the times I hit those unavoidable pot holes.
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