Ride/handling upgrade - E450 / 158" wheelbase

If you are looking to buy new why not look for one built on a Chevy Chassis you wont have any of those problems and don't have to spend a lot of money to get to handle correctly :B

I don't think the Sumos are going to be of any benefit unless the rear springs are overloaded. The rear of a short E-450 is pretty stiff and harsh. An upgrade to the front sway bar would probably more beneficial than upgrading the rear sway bar. Get as much caster as possible on the passenger side and maybe a quarter degree less on the driver side. You won't be able to get too much caster.

The 158" wheelbase on the E450 chassis implies a small Class C?

If this is the situation you're interested in:

We have a 24 foot Class C on a 158" E450. Since day-one, the only downside to it's handling or ride had been up/down pounding in the rear on highway cracks/potholes from it's too-stiff rear leaf springs (but I wanted the overkill E450 chassis for several reasons).

It came stock with front and rear sway bars and a front steering shock. The sway bars and stiff springs - combined with it's wide rear dually stance - provides superb crosswind, highway curve, passing trucks, and roadside curbs/dips side-ways force stability. It "drives like a van", with one-hand steering being easy when safe to do so.

I've since drastically reduced the up/down pounding in the rear by some time ago having a mechanic install Koni's automatically adjusting FSD (Frequency Selective Damping) shocks in just the rear. The front shocks and front steering shock are still the originals after 12 years and 70K+ miles.

bobndot wrote:
.... that sits pretty much level all loaded up, what would the caster be set at ?

My guess, if the caster is still the way it left the factory AND it is level fore and aft....best guess +4.0 to +4.5.

That is based on 1 Degree nose down being +3.25 degrees.

This is a krap shoot guessing game that comes with no guarantees.

I was always a GM guy in the 1500/2500 series but I figured I would give Ford a try in the 450 series but don't ask me why because I have no idea. :B
I have experience with the 550 trucks and they are holding up very well (the diesel engines are a whole other story-emissions ) so I figured the 450 would work too, especially with the V10 pulling such a relatively light load.

Tnx for the alignment info. much appreciated. I would think getting this right is solving most of the issues some people are having .

pnichols wrote:
Since day-one, the only downside to it's handling or ride had been up/down pounding in the rear on highway cracks/potholes from it's too-stiff rear leaf springs (but I wanted the overkill E450 chassis for several reasons).

Driving a unit like yours , this is what I have noticed too. Maybe it's just the nature of the beast but I can live with that if I have to. That was my reason for thinking Sumo's might soften the pounding from hitting the bump stops ?

Sumo's (AFAIK) will replace the OEM bump stops.
If you guys think (in a vehicle like this) the shock upgrade would be a better alternative to the Sumo's, I will certainly look into that option because that too makes sense to me.
I have gone that route with my TC's, Bilstein's and adjustable 9000's and it made a huge difference riding empty as well as more controlled rebound when loaded. They didn't have Sumo's when I owned the TC's only Timbrens but I opted for air bags then went to adding 2 leafs of real steel.

Thank you all so far for your expertise and opinions.

bobndot,

Standard technology "always using the same damping" shocks probably won't take away an under-loaded E450's pounding in the rear.

What I finally figured out was: I want stiff shocks in the rear for their heavy damping in situations such as on gentle roadway dips and rises, roadway curves, going over curbs, going into/out of parking lots, etc.. I want no/very light damping in shocks in the rear (adding practically no damping to the stiff leaf springs) on sharp roadway cracks and potholes.

Standard technology shocks cannot provide a different type of damping in the two situations above.

Cracks and potholes require changing of shock damping to "light" damping. More gradual road surface changes require changing of shock damping to "heavy" damping. Koni's FSD shocks (not their regular technology shocks or competitor's regular technology shocks) adjust automatically in real time to provide either stiff damping, or light damping, depending upon how fast the road surface's vertical change is happening.

You'll never hit the bump stops on the rear of a lightly loaded E-450 which is why the Sumos won't help. If you did hit the bump stops, you'd be shopping for new teeth.

pnichols , thank you for that info, sounds good .

pauldub, re hitting the bump stops, that's what I was wondering . Thanks for confirming that. What im saving in all these add-ons will get me new teeth. :B As long as stay within the white lines I'll be happy.

Thank you.

This is another reason we chose the Winnebago Spirit 25b....the 182" wheelbase on a 25ft motorhome. The perfect combo. Smooth, comfortable, and quiet. Not overloaded. Rides and handles like an SUV. We love it.

Expyinflight wrote:
This is another reason we chose the Winnebago Spirit 25b....the 182" wheelbase on a 25ft motorhome. The perfect combo. Smooth, comfortable, and quiet. Not overloaded. Rides and handles like an SUV. We love it.

For some reason, what you say about your 25b also applies to our 24'7" 24V Spirit on a 158" wheelbase E450. Did Winnebago install your heavy coach items - refrigerator, kitchen galley, generator, propane tank, dual batteries, and four of it's exterior storage bays - between the axles like they did on our 24V?

Your turning radius could be a challenge at times. We come very close to being able to make full U-turns on most residential streets with our 158" wheelbase. We also take our 24V off-highway at times, so we need all the margin from any potential high-centering that we can get.