How big is your fuel tank?

[Desert_Captain]

The auxiliary fuel tank thread in the tow vehicle Forum got me to wondering what most folks have in their Class C's. When we bought our used 2012 Nexus Phantom 23P the dealer said we had 40 gallons which is pretty much the standard tank size on an E350 Ford chassis. I thought that would be fine anticipating 9 to 10 mpg. The gauge and my first couple of trips to the pumps left me more than a little confused, especially when it showed one quarter of tank but took 41 gallons. :S

A little research on the Ford website disclosed that the 55 gallon tank was an option on the 2011 Chassis and happily the original owners went for it. Cruising at 55 to 60 we consistently see 10 mpg both on the Scan Gauge and at the pumps. Sure is nice to know we can go 500 miles and still have a little left. When gas is ridiculously high, vs just plain high, I'll either put 10 gallons in or just keep going. It's nice to have options and we have saved serious dollars with the Gas Buddy App (you do have the Gas Buddy App, right?) and our large tank.

I am curious what the E450's, and others, come with and how that translates into range with the larger heavier rigs (many of which have Toads). :h Also what is your comfort level as to when to take on more fuel? I try to never get below one quarter of a tank as the generator won't run on less than that but if out on the interstate where I know fuel is available and the cost (Gas Buddy again), I'll take it lower.

Folks are frequently seeking advice on what to look for when shopping for a C and this issue rarely is mentioned. For what it's worth, and based on our very positive experience I would put fuel tank size up near the top of the list especially if long trips are contemplated and X2 if you will be pulling a Toad. :C

[pnichols]

judge wrote:
My first couple of trips got me about 9-10 mpg.

That's pretty good mileage for a Ford E450 V10 31 foot Class C.

I'm pushing for slightly above 10 MPG by never traveling above 60 MPH in our 24 foot Ford E450 V10 Itasca Class C.

The reason that I mention E450 is because that chassis has a lower rear differential gear ratio (for more pulling power) than an E350 chassis. This lower gear ratio makes for a slight reduction in mileage unless you drive with a really light foot!

[judge]

I have an E-450 with a 55 gal tank. My first couple of trips got me about 9-10 mpg..

[pnichols]

tenbear wrote:
I suspect that the advertised volume is the absolute maximum that the tank will hold.

That certainly makes sense and is probably the way they should advertise tank capacity.

HOWEVER .... why then don't they design their overall fuel systems to allow one to "easily" get about that much volume into the tank under "average" conditions? That would certainly make sense too ... unless their designs are perhaps for the worst case of filling up from station tanks underground in Alaska in the winter ... but the driver then fairly soon using that gas in the Arizona desert. :h

[Harvard]

For what it is worth, if 55 gallons of gasoline (at 0.7400 g/cc density @60F) were warm up from 60F to 130F it would expand by about (very roughly) 5 percent, that would expand the 55 gallons to 57.75 gallons.

And no, you will NOT get any more miles out of the tank because the increases in temperature has not changed the weight (mass) which in turn establishes the BTU content of the tank full. 🙂

[ronfisherman]

tenbear wrote:

pnichols wrote:
It's the last 5 gallons to get to 55 ..... I think .... now you have me wondering? Maybe I have been getting 60 gallons into it all along!

I suspect that the advertised volume is the absolute maximum that the tank will hold. I remember in a NASCAR movie, I forget the name, they mentioned using 1" diameter line from the tank to the engine to increase the capacity. I doubt that RV manufacturers do this.

My tank is advertised by GM as 80 gallons. There is a tag on side of tank that states 109 gallons. Extra size must be for expansion. Most I have ever put in it was 72 gallons. Needle on fuel gauge was just above empty.

[tenbear]

pnichols wrote:
It's the last 5 gallons to get to 55 ..... I think .... now you have me wondering? Maybe I have been getting 60 gallons into it all along!

I suspect that the advertised volume is the absolute maximum that the tank will hold. I remember in a NASCAR movie, I forget the name, they mentioned using 1" diameter line from the tank to the engine to increase the capacity. I doubt that RV manufacturers do this.

[tarnold]

1997 E350 V10 35 gal. Are all gas pump flows the same? When in Canada never could get the pump to run by "setting the trigger". Had to nurse every gallon in by slowly squeezing the trigger. Seems like all stations down south will run till almost completly full.

[pnichols]

It's the last 5 gallons to get to 55 ..... I think .... now you have me wondering? Maybe I have been getting 60 gallons into it all along!

[Harvard]

Quote: "Of course how I "keep it near the top" is by trickle-filling it each time to make sure the last 5 gallons gets in!!"

About that last 5 gallons, is it the last 50 to 55 gallons OR is it a bonus 55 to 60 gallons on the E series ?

[pnichols]

maillemaker wrote:
Ultimately it's the size of your wallet that matters.

STeve

Well .... kindof.

I never push the level in our 55 gallon tank to get gas cheaper. We keep it near the top just in case ... you never know what can happen out on the open road. i.e. We traveled with friends once and their rig blew a transmission so they of course couldn't get near a gas station for days. What if they would have had to live in their rig for, say, 48 hours by continuous running of their built-in generator for heating, cooling, and maybe even cooking?

Of course how I "keep it near the top" is by trickle-filling it each time to make sure the last 5 gallons gets in!! 😉

[maillemaker]

Ultimately it's the size of your wallet that matters.

STeve

[lfcjasp]

An E350, 55 gallon tank.

[TyroneandGladys]

Two 18 gallon tanks

[scroller95969]

04 Chevy 6.0
Fleetwood Tioga 22B
35 gallons