Dual fuel tank in a 04 ranger?

[RonD]

What are your thoughts on a tank, skid plate combo that is visible from behind the truck, good , bad , no important? I know that some ford trucks ran a second tank, had a switch on the dash to change over from one tank to the other and had a valve for the fuel line , where these just trucks that had an inline pump and not a in the tank pump???

Skid plate is always a good idea for fuel tanks, even on-road, metal debris is picked up by vehicles in front of you, or even your front tires, and starts bouncing between road and under vehicle surfaces, it can do some damage.

Yes, in the "old days" the switch on the dash would do two things, it would switch the fuel gauge from one tank to the other and activate a solenoid that would switch fuel lines from one tank to the other.
Solenoids could just have 2 IN x 1 OUT, 3 port, or also have Return line, so 4 IN x 2 OUT, 6 port
And electric switch on dash would also switch power to chosen in-tank fuel pump.
That stuff is all available and pretty generic, works on any vehicle.

Problem is still the EVAP system, which does NOT like sudden pressure changes while running, so switching tanks on the fly would be the problem, along with the cost of duplicating the EVAP parts on the second AUX tank.

The "Y" filler removes that problem, I would think.
Because the two tanks share common pressure when gas cap is on draining one and then switching to the other one, dash board switch, shouldn't cause it to "raise an eyebrow" as there would be on pressure change in the sensors in the main tank.

 

[tac1015]

Ok, pulled the spare and the frame is 27 inches or so on the inside, front to back could be about 24 inches and from the frame brace that holds the spare the bottom of the tank at 5 inches is about at the bottom of the rear bumper, that only give about 14 gallons. Can make the tank longer , closer to the diff but would have to make notches for the shocks , not hard to do, could add another 3 gallons. The filler of the second tank would have to run along the outside of the frame ,parallel to the bed seam and could then turn to the filler neck and the vent line would follow, easy enough. Could make the tank deeper, start out at 5 inch in the rear and increase the depth to 8 inch or so, will have to lay it out and get a cross section of it to get a volume of this tank.

What I think, might not be for everyone , is to remove the frame brace that holds the spare, and make 2 new ones to take its place. Making the frame pcs is a no brainer for me , do that stuff all day. It would take removing the stock riveted on brace, replace with the 2 new, but stronger braces but this would involve removing the bed drilling or cutting off the stock rivets and bolting in the 2 new ones. Again if I went this route it wouldn't bother me, the bed comes off in just a few minutes and removing the stock spare support would allow the tank to be taller, provide a vent area in the new tank and would be the place for the filler to enter the tank and give the tank breathing area. I want to see if this second tank can be done with as little modification to the stock truck as possible. This would make it easier for other to install and make for an easier install, but if I want as much volume as I can I would do it, don't know about anyone else , but I would do it. Still not sure yet the best way to get the gas out, maybe an extra stock pump setup and an switch??? Will keep looking into first making the tank to fit and to go from there.

If anyone has thoughts on others doing something like this or any different way to do it , I am open to suggestions.

 

[tac1015]

Well did the trusty cardboard model of the tank and a 24 x 27 x 5 to 8 inch tank give about 19 gallons. A tank this size gets close to the exhaust , so will have to take the corner off to clear and that will lose a little. If I make the tank 12 inches instead of 8 that give about 30 gallons, now that's not so bad. To make a 12 inch tank that go's up instead of down I would have to make the new frame cross members. The frame in the rear is about 4 inches thick in the back so for the extra 11 gallons I think it is worth it. I will finish the cardboard tank and add a little in the height to put some of the tank into the area of the spare cross brace and add a little more in volume and try to figure out how to get the filler in the tank above the frame rail.

Any thoughts on 20 or 30 plus gallon size of tanks??? The 20 or so gallon would be the easier of the 2, could make a strap that will attach to the stock frame cross brace to support the tank and would just require drill of some hole to get it to mount to the frame, but I like the idea of as much volume as reasonably possible so I might try to make 2 tanks, one smaller and one larger to see what I think.

 

[RonD]

20 gallons is about 160lbs of fuel, 30gal = 240lbs, make sure to have baffles in the tank to prevent sloshing, the weight being behind the axle could push back end sideways on a slippery road, if it sloshes.
Put 200lbs of weight in the bed, above where fuel tank will be, to see if truck still sits level, it should but worth seeing ahead of time.

 

[don4331]

Gentlemen:

Pardon my dumb questions, but I am interested in this.

Assumption: 2 fillers; one in front of rear wheel; other behind. Styleside body

If you run a hose from the front tank filler vent line to the rear tank filler vent line; wouldn't it address the evaporation canister issues? Just put a 'T' in the existing line, and run a tube over the wheel well- ideally steel tube with short rubber ends. We want vent line raised so it doesn't collect any liquids and stop air from flowing from one tank to the other. Would a line "T'd" into filler line let you get away with just a single filler? Running just inside frame with appropriate shielding to protect from stray rock.

Then put pump/sender in rear tank, check valves on lines out of front and rear tanks; switch in cab to flip between front and rear tanks.

I have to admit, I was thinking thin tank - only 2.75" at spare location with only left front corner deep*. Method in my madness: I was swapping the 245/75R16 for a 175/90R18 (Hyundai Genesis compact spare) <I can't run without a spare in some the rural country I visit - no cell coverage - but want to be able to use truck box...>

As promised, update on sag, with 200lbs (more/less) in location of rear tank. Ranger in question is '98 stepside splash (1,100lb springs). Front RISE - 7mm (~1/4"); Rear sag - 37mm (1½") Front/rear measurement at bumper trim (extreme ends of vehicle).

*I have long box and therefore have some extra space full width to work with.