Forum Discussion

rbreak's avatar
rbreak
Explorer
May 23, 2016

Improving harsh ride?

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)
  • 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.
  • 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...
  • 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.
  • 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

  • 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).