EPA/NHTSA rule affect motorhome MPG

[Chance]

Is this good, bad, or won't make much difference?

RVIA: EPA-NHTSA Rule Less Rigid on Motorhomes | RV Business


They are only talking about 5 to 10 percent, which doesn't seem like much of an improvement. Still, it would be nice if MHs were a little more fuel efficient; provided it doesn't drive cost much higher.

[JamieGeek]

I think the 5 to 10 percent will surprisingly match the mpg improvements of the chassis that they are built on (since the trucks that motorhomes are based off of will have to also match those figures).

It will mean the end of the V-10--will probably see more Transit based class C's and ones built on the new Ford V-8, perhaps even one of the Ecoboost V-6's will make it into Class C's.

[Chance]

Jamie, I'd like to know how they will measure improvement when the chassis and house are built by two separate companies. Ford could make the chassis 10% more efficient and then have a larger and heavier RV built on it by others, offsetting gains. Does rule apply to chassis or completed motorhome?


By the way, the Ford 6.2-liter V8 as tuned for 2017 Super Duty has excellent power and torque ratings. I doubt too many will miss the 2-valve V10 in their Axis or Class C. That revision alone should make a significant difference in MPG.

[JamieGeek]

Originally Posted by Chance

Ford could make the chassis 10% more efficient and then have a larger and heavier RV built on it by others, offsetting gains.

Except that Ford will have to make it 10% more efficient based on the GVWR and GCWR. As long as the RV (and trucks) built on it are under the GVWR they still should be able to achieve the 10%.

Note that the stripped chassis also finds its way into Fedex, Food, MacTools, etc. trucks as well. (Ambulances too..)

[Chance]

Originally Posted by JamieGeek

Except that Ford will have to make it 10% more efficient based on the GVWR and GCWR. As long as the RV (and trucks) built on it are under the GVWR they still should be able to achieve the 10%.

Note that the stripped chassis also finds its way into Fedex, Food, MacTools, etc. trucks as well. (Ambulances too..)

Even so, I'm not sure how that's going to be regulated because weight alone is not a good indicator of fuel economy on the highway, where many motorhomes end up racking up miles.

For example, an E-450 cutaway could be used under a low profile and narrow Class B+, or could also end up under a wide body Class C with the aerodynamics of a brick.


Mostly I'm curious if the RV industry will have regulatory and marketplace incentives to make RVs more fuel efficient, or if they will simply find a way to circumvent the intent of the new policy. My personal wish would be for an Axis-size MH (or slightly smaller like the Sprinter-based Winnebago) that could do an honest 12 MPG at steady 62 MPH. That seems very doable in the timeframe being discussed.

Having an EPA highway rating similar to those of cars could also help. That information may influence buyers.