Class A V-10 mileage

RLS7201 wrote:

A1ARealtorRick wrote:
So, if well-engineered cars can have 8, 9, and 10-speed automatic transmissions in an effort to maximize fuel economy and enhance overall performance in the process, why can't motorhomes?

The steep throttle plate angle required to move 20,000+ lbs down the road, would not allow 10 speed transmissions to achieve the higher gear.

Richard

Consumers would be surprised to learn that a 8,9 and 10 speed transmission will never use the higher gears unless you were at extremely high speeds! And yes in an RV because the throttle is always at least At 70%, a 10 speed trans would barely hit 6th. In fact I noticed with mine I’m usually in 3rd most of the time, rarely in 5th except with a tail wind or downhill. I’m convinced the programming Ford puts in the ECM is marginal at best! I can hear the throttle opens when it wants even when the pedal is on the floor. Which is why Next year I’ll be getting a 5star tune to fix Fords poor attempt. If they made these the way they should have at the very minimum Tow Haul would be defaulted to always on. They build these chassis as generic. A UPS truck will never weigh as much as a fully loaded RV. Which is why these things are terrible on power. I also believe that these are under geared. My coach has 4.30’s. Which is also available on an F250 with a V-10 and 5speed, and those have smaller diameter tires. There again these are built as generic so a 4.30 works great at lighter weights, but not at all good for fully loaded weights!

There is no reason I should lose 15mph on a slight grade coming out of a river vallley!

RLS7201 wrote:

A1ARealtorRick wrote:
So, if well-engineered cars can have 8, 9, and 10-speed automatic transmissions in an effort to maximize fuel economy and enhance overall performance in the process, why can't motorhomes?

The steep throttle plate angle required to move 20,000+ lbs down the road, would not allow 10 speed transmissions to achieve the higher gear.

Richard

OK, that's understandable. I still feel as though manufacturers in some way could increase fuel economy enough to make a difference. Like the Ford V-10 for example. How many years has it been the 'same engine' without updates and tweaking? Ford has a pretty good deal going, providing the rolling chassis' for the motorhome manufacturers, and without tremendous backlash, why would they see a need to make the engine/transmission combo more fuel efficient? Just an observation.

I normally get between 5.5 and 7.5 MPG going to Colorado and back. I feel it is uphill most of the way there and uphill most of the way home(haha). Engine is working great at 65 mph. My toad is a 4 door Jeep Wrangler.

A1ARealtorRick wrote:
So, if well-engineered cars can have 8, 9, and 10-speed automatic transmissions in an effort to maximize fuel economy and enhance overall performance in the process, why can't motorhomes?

The steep throttle plate angle required to move 20,000+ lbs down the road, would not allow 10 speed transmissions to achieve the higher gear.

Richard

Too many variables affect mileage, it's a big box with considerable weight, I get 6.5 to 8 MPG pulling a wrangler 2D TJ. Like to run around 60+-.

there trucks with a pretty face.

So, if well-engineered cars can have 8, 9, and 10-speed automatic transmissions in an effort to maximize fuel economy and enhance overall performance in the process, why can't motorhomes?

I had a 1997 460 F250. 7-8mpg......empty. But, that was a lot better than mt 37' 454 P30 motorhome....5mpg.....on a flat road. Compare that to my plug-in Prius..... Maybe we'll have an electric truck here someday?