Off Road Class C Motorhome and Extended Tray

Vikr wrote:
I disagree

They are not a great Off Road vehicle, their low ground clearance weighs against it. fast attack yes. That is why Expedition Vehicles have much greater ground clearance.
Other vehicles were used as Off Road Vehicles in Afghanistan/Iraq. Humvees mainly convoy support.New US off Road reconnisance vehicle.

The Humvee is not a great Off Road vehicle. it was designed as a fast attack vehicle, to be used in manly desert conditions. That is why used ones are not used as Off Road Vehicles, were not designed as such.

I disagree.

PNichols wrote:
In no way am/was I overall comparing an E450 van to those weird looking, purpose-built, ultra high dollar expedition vehicles in raw ground obstacle clearance capability and traction capability.

What I was trying to bring attention to in my post(s) above was that they, geometry-wise, look a bit too narrow for their heights

There not. What they may appear to you has nothing to do with their performance.

After looking at those two vastly different profiles - ask yourself which design you'd rather have in a vehicle that you are tipped sideways in on the side of a sand dune, or equivalent side-slope?

The Humvee is not a great Off Road vehicle. it was designed as a fast attack vehicle, to be used in manly desert conditions. That is why used ones are not used as Off Road Vehicles, were not designed as such.

By the way and for what it's worth, HumVees also have a relatively unknown design trump that hardly any, or no, expedition vehicles have - universal joints right at each wheel with the wheel's drive axle immediately sloping steeply upwards right from the wheel to meet high differentials - no horizontal drive axle coming out from the wheels to get banged up. This is NOT merely "independent suspension", as the differentials are up high up and not at all inline with the wheels when the vehicle is at rest.

You can get that with some Expedition vehicles but does not matter that much.

We are every bit as "rugged" and "high above the ground" as the vast majority of pickups and SUVs (...that is, "U.S." pickups and SUVs, don't know about Australian ones...). However my main point is, our E450 rig has a wide stance so as to help us feel secure on side-slopes and in high side-winds.

No you are not.It does not have a wide stance and is unstable in winds. Your Rig is a road going Class C Motorhome that can run on graded dirt roads, like many cars and Motorhomes in including Class A's , nothing more.In really Off Road Conditions it is useless.
Class A "Off Road" Motorhome. By the way I had a chance to drive a E450 Tioga Rental from Apollo Motohomes while going across the US. I was not the main driver but had a chance to drive it on a Freeway(kept 60mph), it was a barge to drive and yes wind buffeting was extremely noticeable when being passed by Class A trucks.

Robert,

In no way am/was I overall comparing an E450 van to those weird looking, purpose-built, ultra high dollar expedition vehicles in raw ground obstacle clearance capability and traction capability.

What I was trying to bring attention to in my post(s) above was that they, geometry-wise, look a bit too narrow for their heights. Hence my suggestion that one compare - for the sake of clarity - a vehicle like the Humvee's profile from the front or back ... to the profile from the front or back of those weird looking, purpose-built, ultra high dollar expedition vehicles. After looking at those two vastly different profiles - ask yourself which design you'd rather have in a vehicle that you are tipped sideways in on the side of a sand dune, or equivalent side-slope?

As you know, it's tire height that makes for raw ground clearance - not coach height. So tall tires will always trump "lifting of the coach components" in importance for gaining of ground clearance to minimize vehicle damage or traction hangups. Those vehicles in expedition photos not only have tall tires (as they should) - but their coach components are also often lifted way up towards the sky. The Humvee has tall tires for outstanding protection of vehicle drive components and deep-rut traction - but a very low coach component profile for superb over-the-top lateral stability.

By the way and for what it's worth, HumVees also have a relatively unknown design trump that hardly any, or no, expedition vehicles have - universal joints right at each wheel with the wheel's drive axle immediately sloping steeply upwards right from the wheel to meet high differentials - no horizontal drive axle coming out from the wheels to get banged up. This is NOT merely "independent suspension", as the differentials are up high up and not at all inline with the wheels when the vehicle is at rest.

For what it's worth, my E450 Class C doesn't quite look like the classic Class C in your photo above (your photo may be an E350?): My 24 foot coach probably sits higher because it's using less of the E450's gross weight carrying capacity so that the springs are compressed less. I'm also using over-size (tallness-wise) tires than stock, to gain raw ground clearance on all components. The rear overhang (the "approach angle" in offroad vehicle parlance) of our Class C is not that as shown in your (typical) Class C photo. Our coach's side paneling immediately starts to angle upwards starting right from the rear wheels on back ... the paneling DOES NOT continue on straight back aways and then begin sloping up, as in your Class C photo. This is a subtle difference to help prevent some coach paneling and rear outside storage cabinet damage from rocks, ruts or when coming down off the end of slopes. Also just to set the record straight, the stock E450 chassis design makes it's "ground clearance" easily equal to that of millions of stock pickup trucks and SUVs (w/no lifts and w/stock tires) ... which folks run all over the place with offroad. We do this with our Class C too ... just slower so we don't bang everything around inside the cabinets or jar our dinette loose from the flooring. We are every bit as "rugged" and "high above the ground" as the vast majority of pickups and SUVs (...that is, "U.S." pickups and SUVs, don't know about Australian ones...). However my main point is, our E450 rig has a wide stance so as to help us feel secure on side-slopes and in high side-winds.

Pnichols wrote:
My humble little E450 Itasca Class C has everything heavy (except for the microwave oven and any stuff I load in the it's upper cabinets) way down low close to, or equal to, the height of the E450's frame rails ... so it's COG is very low.so it's COG is very low. However it's rear track is also very wide - wider than the E350's track - and probably right at the U.S. highway legal maximum - the same as the track on big rig trailers.

No it is not that is why it cannot go Off Road effectively.Its rear overhang is too excessive, its ground clearance is virtually non-existant, its actual COG is too high(reason E450 Vans are blown around by passing trucks). Whether you have items near the frame rails is not what really matters It is how the drive train gearbox engine etc are packaged.
A wide track does not mean it can be an effective Off Roader. A Unimog does not have a wide track but is very effective Off Road and is the choice of people who want an Expedition vehicle An E450 is a Class C Van built for roads, Its steering is vague as well , something you do not want on a Off Road Van. It is the antitheses of an Off Road Van.



This is a whale by comparison

That off road motorhome looks rugged and I like the rear tray. I can picture it in weather where you are boondocking and don't want to be out on the muddy ground. Also covers you from rain/snow. Some toyhauler rear doors also suspend as decks but don't have rails or cover.

Unimogs are the shizzle!

Jose

Have you not ever heard of or seen a Unimog before? They are extremely capable and stable, yet look alot like the above 4x4 RV.

Robert,

Expanding just a bit on your comment above: It's not purely a COG issue. It has to do with the height of the COG along with the distance apart of the support points ("tires") - both longitudinally and laterally - for the COG. The points of support distance apart being of course controlled by how long each axle is (i.e. a vehicle's "track" -> lateral points of support) and how far apart the front and rear axels are from each other (i.e. a vehicle's "wheelbase" -> longitudinal points of support).

Some of those narrow offroad/expedition type vehicles - even with their low height COGs - still look to me like they could stand a bit wider front and rear track ... especially in some of the photos in which they are tipping sideways on sand dunes.

My humble little E450 Itasca Class C has everything heavy (except for the microwave oven and any stuff I load in the it's upper cabinets) way down low close to, or equal to, the height of the E450's frame rails ... so it's COG is very low. However it's rear track is also very wide - wider than the E350's track - and probably right at the U.S. highway legal maximum - the same as the track on big rig trailers.

This wide track of course would not be good for ease of driving in many cities, villages, and on the mud single rear wheel tracks in countries outside the U.S., but ... it sure makes me feel stable when we're on canted roads out in the desert.

A great example of what I'm talking about regarding the geometry of COG versus the distance between it's support points is the U.S. military's HumVee. Notice that it's very wide and very long as compared to it's height. It's of course purpose-engineered for maximum offroad stability .... exactly the way an ultimate offroad RV should be.

Of course for an offroad RV to approach the stability of a HumVee would require the RV to be a "pop-up" or "crank-up" living area design. There are a few U.S. (and Australian?) RV models that are of this type. As a U.S. example, Tiger used to offer a 4X4 pup-up Class C design with it's coach built directly onto the truck frame ... for a very low COG ... definitely an offroad stability improvement over a standard truck camper. Unfortunately this Tiger model's track was only that of a stock U.S. SRW truck.

pnichols wrote:
Of course, those ultra-tall and narrow caravan things in other countries make me think they're gonna tip over any second, but ... you gotta love their rear approach angles!

They are built for Off Road and their COG is a lot lower than say a US TC.