[slowmover]

Sorry I missed this earlier.

The 53’ trailers I pull with an aero Class 8 tractor vary from no aero mods, to those with full skirts and tail. The difference is somewhat slight, but telling as to the extra work I’ll have to do that day. I’d always prefer full aero.

The biggest change would be to have a flat-front trailer hooked to a non aero tractor. It’s unreal how much force is necessary to pull that down the highway. I speak of how noticeable this is to the driver. How hard it is to show decent FE on the gauge.

Some cattle-haulers prefer this set-up as it’s literally an aid to braking (moving livestock a world of its own).

I see that ambulance and the first thing I think I’d do is to add (brand name) Nose Cone to the body. Get that problem out the way and the feel to the vehicle changes rapidly.

Steering slop and old shocks can’t be tolerated. Same for worn body bushings. Steering corrections per 100-miles is a measurable FE effect according to industry. Aero won’t help much until your steering degree of angle and duration x corrections is minimized.

Until you’ve minimized the flat front effect with some aero, and made steering AND handling brand-new, don’t expect aero band-aids to do much for you. That comes AFTER the driver can feel what’s happening thru the wheel. Sensitivity.

As to the rest, ORBYWAN modified a Class C motorhome on these pages a while back. Read all those threads. (Great stuff above in this thread).

For the vehicle rear, a custom trailer that followed the lines suggested by Aerohead to cause a passenger bus to be able to run 100-mph on the same fuel would be the right approach.

Or study the design of a (brand name) Trailer Tail.

Straight trucks (non-articulated) are terrible on the highway. It’s the wind that is not released by the body until passing AGAINST the air moving cross-ways underneath. I feel certain that an air dam and side skirts are a worthwhile investigation at a low cost and are easily removed. Will smooth the vehicle passage so that nose cone and trailer tail devices can more easily be evaluated.

1). Steering
2) Handling
3) Body to ground mods
4) Entry & Exit Mods

One has to have great feel at the wheel. Like locating the direction of a sound.

As to the RV as RV:

A motorhome is inefficient in all respects. It’s weight, complexity, and shape keep its initial cost and operating costs high and camping utility low. Only newbies love them.

If my 63’ combined rig RV can average 15-mpg (17,000-lbs), sleep six with far more storage, capacities and features, where is the advantage of a commercial truck-based RV?

As 13-mpg isn’t bad. If driving a few extra feet off-road is really worth it.

The formula for total cost is annual nights aboard into years of service. Answer that for relative cost and the balance falls into place. Value.

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