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Do newer trucks still come with a a dual fuel tank option these days?

You know, where you switch from one tank to the other by moving a valve lever, usually under the driver’s seat? The valve is fairly complicated gadget b/c it has to switch both the fuel supply lines and the fuel return lines. Four inputs, two outputs. My early 70’s Ford truck uses that sort of valve, and it is starting to leak a little gasoline inside the cab. So I need to replace the valve and I’m thinking it might be easier to adapt a replacement valve from a newer truck rather than source a direct replacement part. What do you think?

Something like this maybe?

Nope. Modern day trucks just have one large gas tank. Well I don’t know that I’d say modern. I have a Chevy 1/2 ton pickup with a single 30 gallon tank but it’s a 1989.

My father’s motorhome, built on a 1985 Ford E-350 Econoline Van chassis, had dual gas tanks, but as I remember it, it had a simple toggle switch under the dashboard to switch tanks. Now that I think of it, 1985 was over 30 years ago, so nevermind, I guess. Oops.

That appears to be electrical, not mechanical. Although none of the photos show an electrical connection either.

the gas tanks are huge now,some of them hold half a bbl ,you just dont hear much about them now,I would have thought a lot of auxiliary tanks would have been self equalizing ,some of the transfer switches were rather crude ,some people just use the main tank and do away with the aux system when problems occur .

Dual tanks went away in early-mid 90’s for the most part. I’ve never personally seen a truck with dual tanks that actually worked properly. These days manufacturers just use a single large fuel tank, it’s a much better arrangement IMHO.,

Single tanks is certainly less to go wrong, but my 93 f250 with dual tanks, died due to rusted brake lines, oil pan and exhaust manifold. My newer o4 or 3 has cng and regular gas tank, but due to whatever I have to drive 15 miles to get cng, work truck so just regular gas.

Guys, WTH . . . ?!

Ever heard of fleet vehicles . . . ?!

Probably half the trucks in my fleet are dual tank

And no, George, they don’t have a switch and/or lever to switch between tanks. That went away some time ago

For the record, the vehicles I’m talking about are cab/chassis, incomplete, etc. Whatever you prefer to call them

But they’re all body-on-frame, so they could be called trucks. Not pickup trucks, perhaps, but they’re still trucks

I was walking through a new car/truck dealer (GM) with a friend a few weeks ago and walked past a line of perhaps ten new chassis with no beds/attachments yet that all had dual tanks. They were all the size of a full size pickup chassis, some with crew cabs some not. Yeah, they still make them.

Thanks for the ideas and info. I’ve found a source for a new fuel valve part that switches between two ports, I’d call it a three port valve. For about $40, so the price is right. If I gang two of those together I’ll get the functionality I need. It’s solenoid operated, so I’d use an electrical dashboard switch rather than a valve lever. I’m not sure how that works exactly, for example does the solenoid have to be energized all the time the truck is on?

“. . . they don’t have a switch and/or lever to switch between tanks.” So how do you switch between tanks? Does the computer do it automatically, and if so, when you get gas, how do you know which tank to fill?

Two tanks still seems like a good idea in certain applications to me, like a motorhome. I remember the auxiliary power generator only drew fuel from the larger rear tank, so if you inadvertently ran out the tank running the generator, you still had the front tank, providing you hadn’t run that empty driving the previous day. :wink:

I imagine this could prove useful in situations if the engine can run on E-85 or E-15 but the auxiliary generator cannot.

Thanks for bringing back some fond memories of long ago. I remember when my father bought his motorhome after he retired, the salesman telling him he could run the cheaper regular (leaded) gas because the large engine / chassis classified the vehicle such that it didn’t have catalytic converters. It became kind of a moot point anyway, after about the second summer he had it, the sale of leaded gas was pretty much phased out. :smile:

Some motorcycles still have a fuel reserve switch, but they only use one fuel tank and two fuel lines, and they use this in lieu of a fuel gauge. My newest motorcycle has a fuel light rather than a reserve switch, which I greatly appreciate, because I never liked the feeling of losing power unexpectedly.


Aren’t those duel fuel tanks connected, so they function like one large fuel tank? If you fill only one up, fuel will run from one to the other, and then both will be half full.

Edit: @Ed_Frugal, I think I just answered your question.

Some motorcycles still have a fuel reserve switch, but they only use one fuel tank and two fuel lines...

All of my motorcycles with a reserve had a single fuel line and valve (ON-OFF-RES) and a stand pipe in the tank. Switching to reserve valved in the fuel below the top of the stand pipe.

My old trumpet has 2 lined and 2 petcocks that feed the carb. the reserve is the gas in the tank below the hump for mounting to the frame.


you’re definitely on the right track :smiley:

They have 2 filler necks, so you have to fill both tanks individually

The front tank is the main fuel tank, meaning it’s the one that supplies fuel to the engine

There is a fuel transfer pump, which serves to transfer fuel from the rear to the front tank, so that you theoretically don’t have an empty front tank, but a full rear tank. Unfortunately, it’s not uncommon for the transfer pump to fail . . . :frowning:

And the reading on the gauge is “averaged” out, so that it reflects both tanks

If the two tanks are connected and transfer the fuel automatically then why have two tanks anyway? Just have one big tank. I was thinking of commercial or recreational applications where you’d run an auxiliary generator on site. If the generator is only connected to one tank it would prevent you from becoming stranded. By the way welcome back @Whitey haven’t heard from ya in a while :smiley:

Why have two tanks? How about space restrictions that eliminate a large tank.

@Ed_Frugal, semis (road tractors) have two connected fuel tanks for a few different reasons. One probably has to do with design and weight distribution. The Volvo I used to drive had two 150 gallon tanks, one on each side. The second reason is so you can dispense fuel faster. Most truck stops have pumps on both sides of the fuel lane so you can have two going at the same time. The third reason likely has something to do with available space. Where would you put one 300 gallon fuel tank on a semi?