Gas tank size in Class B on 2021 Ram Promaster 2500: is 24 gallons enough?

[johnmacatlarge]

Hi Everyone,
Just bought a new camper van built on a 2021 Ram Promaster 2500 high roof. It has the stock 24 gallon gas tank. It looks like ther is a 40 gallon gas tank available. I am trying to decide if it is worth installing the 40 gallon or not. We are headed on a summer around the country trip and so this would be something to do now. The van lists 16 to 18 MPG. I have no idea what I will really get, but assuming 16 MPG then the 24 gallon tank would be good for 384 miles which seems like it is a bit short. We would clearly gas up on every notable driving day.
The 40 gallon tank would be good for 640 miles which seems much more convenient.
Any thoughts on 24 gallons versus 40 gallons? What is the the norm?

 

[Chargerman]

Can’t imagine that you will be getting that posted mileage considering the rig is weighted down pretty well. That tank is small considering the rig size but replacing it with a 40 gallon tank may be pretty costly. If you end up getting 300 miles per tank I would think you would be ready for a stretch and some lunch by then so I wouldn’t think it would really be inconvenient.

 

[Kevin D Pem]

I'm with you! My Ram has 35 gallon tank and it offers me the ability to travel on if the locals are price gouging.

 

[Rosy]

I see no disadvantage to the bigger gas tank.

 

[sanda]

When traveling long distances between stations 24 gallons may not get you there. One example is Alaska.

 

[johnmacatlarge]

Can’t imagine that you will be getting that posted mileage considering the rig is weighted down pretty well. That tank is small considering the rig size but replacing it with a 40 gallon tank may be pretty costly. If you end up getting 300 miles per tank I would think you would be ready for a stretch and some lunch by then so I wouldn’t think it would really be inconvenient.

I drove it home last night (in awindy rain storm here in Northern Cal). I reset the trip meter for the trip.
It was 55 miles with the last 25 on a freeway cruising. Before the freeway I was getting 14ish.
I managed to get up to 16.5 for a while but then drifted back to 15.5. Still, I never used cruise control and I could tell that unless you are very very delicate with acceleration, it will be very hard to get to the 16 number let alone the 18 number.

 

[johnmacatlarge]

I see no disadvantage to the bigger gas tank.

It looks like the tank itself is going to run about $1400 ( I have not found the specific tank yet but they all seem to be about that much). But the labor is probably not going to be cheap. These things wrap around the frame there must be a bunch of stuff to disconnect and reconnect to do it.
But, yes, I would say no disadvantage other than the cost.

 

[sanda]

1 other issue is reading the computer readout for your mileage. Having owned 7 vehicles with computed mpg none were ever accurate. They all showed higher mpg than hand calculated. You won't know your real mileage until you can run a tank of fuel and compare the numbers.

 

[Knobs]

1 other issue is reading the computer readout for your mileage. Having owned 7 vehicles with computed mpg none were ever accurate. They all showed higher mpg than hand calculated. You won't know your real mileage until you can run a tank of fuel and compare the numbers.

Hush! I'd rather be fooled!

 

[johnmacatlarge]

Memorial Day Weekend Trip up to Oregon and back in the Ram Promaster 2500 has showmn 16.3 to 16.7 mpg based on auto shutoff fill ups. The trip computer on the van itself is (amazingly) showing about the same numbers.