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Extra Fuel Tank

11K views 7 replies 4 participants last post by  10%More 
#1 ·
Actually wanted to be #1 to post something here. Hate to be #2...think about it.



Put an RDS fuel tank into my truck for obvious reasons. 26 gallons is fine if you don't tow. The normal tank range is well over 600 miles. I tow. That's another story. It's obvious you need another tank.

The model I chose is 20 gallons. Fits right in front of the wheel-well and takes up little bed space. Plumbing it to the fuel filler is not all that hard. Sure there's a little "pucker factor" when you take off the soft hose to the tank and get ready to cut. Even more when the hose clamp you slid over what's left falls down to the tank. You can reach it, do it and conquer stretching the old filler tube over the RDS filler piece. It all fits.



That silver thing is the RDS filler neck piece you install. There's a check- valve at the fill junction that shuts off when the main line is full. No spill. Everything works.

At the bottom of the tank is a simple shut-off valve. In this case it's for a turn-on. I like "turn-ons. Installed two fuel filters in the lines. One, now look to the right at the bottom of this picture, is for the fuel going into the main tank.



The other helped when I did "stupid". The factory fuel cap has a key and is non-vented. This picture shows a different cap. Smacked the keyed one with a piece of plywood I slid in. Knew I would someday break the key off or I would lose it, so I replace the thing with an old junk cap I found. No fuel flow.

Those three tubes have caps on them. Two of the tubes are drain tubes if you want to syphon or pump out. I used the third drain at the bottom with the valve. The other top one is a vent. Darn thing had a cap also. No vent = no drain. I stuck a little piece of fuel hose on it with a small filter at the end so dirt does not get in. No splash out and no leaks. Fuel flows fast.

Couple of "nices" now. Look at the fuel gauge. Nice, heh? It also works.
Filling is easy for me because I have a cap window that opens up from the side. No bed cap and you might want the keyed cap the tank comes with.

The other "nice" is the whole thing, including the time and effort I took to post this. Hope it helps.
 
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#3 ·
Never seen this done on a truck before, but its a great idea. Most people don't really need that extra fuel, but at the same time its nice to not have to fill up as often. And you can take advantage of lower fuel prices by buying more then. How much range do you get while towing now that you have the extra fuel tank?
 
#5 ·
Two answers coming up but first - this is no big deal. Sounds like you think it's a major operation or expense. Since the early 90's I have had diesel pickups. ALL had extra fuel tanks. My early GM had two under-the-bed tanks. I had to put extra bed tanks into my Duramax and the Cummins. I literally would not want the truck without them. Finding and stopping for fuel is a bummer, especially if you run all over.

Think this entire set-up cost me about $325. That's for the tank and the fuel filler assembly. Installation is a breeze and you can easily remove it to use elsewhere. I did not remove my last tank as it was 30 gallons and I did not want another that large as it took up too much bed space.

46 gallons total now. How far will that tow? What am I towing and what is my fuel mileage times 46 and subtracting some for reserve? All tows are different. You do the math or go back to third grade and pay attention this time.

As for this being unusual, I think it is the norm. Most all pickups I have seen, and I do mean ALL, use in-bed tanks if they use their trucks for more than local play. Most of those metal tool boxes behind the cab of diesel pickups have a fuel compartment in them. Now this is NOT true for gas trucks.

Gas trucks rarely tow much of anything for all the reasons big trucks are diesel. Hauling gas around can be dangerous. Those with gas trucks are not really into hauling and trucking anyhow. If they were, they would have a diesel.

This little 1500 Ecodiesel can tow within it's limitations. If your camper or toy-hauler tow means you get 10 mpg, think about how miserable it would be to be forced to find fuel every couple hundred miles. You literally could not have a reasonable run out West or around the New England area where fuel stops are either far apart or near unavailable.

Then there's the issue of price. GOD help you if you have to haul in California. Prices are stupid there. Fuel up, get in, get out. That's how you deal with that **** hole. That and an extra fuel tank.
 
#7 ·
Been running it the past few days with the petcock open and a full tank showing. No leaks and just a little drop in the extra fuel tank gauge.

Topped it off today, turned the extra tank off and tried to top off the factory tank. Literally nothing would go in. Full as shown.

No leaks, no nonsense and it really is a "no-brainer" installation.
 
#8 ·
FYI...The extra fuel filter I added between this tank and the main tank plugged up. Running back from North Carolina and turned it on. Fuel drop did not keep up with consumption.

Back home I took the filter off and it was black/plugged. Not sure why. Possible the one I bought is not for diesel and came apart. Possible the tank had debris from construction. Doubt it was bad fuel as bad as I saw the debris in it.

Threw the extra filter out and am now running straight pipe to the main tank. It dumps fast so now it's all on the main truck fuel filter to carry the load.
 
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