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Auxiliary Gas Tank

88K views 141 replies 30 participants last post by  HueyPilotVN  
#1 · (Edited)
I think I have found a solution for adding an auxiliary gas tank to my Commander. There is a business that is dedicated to performing this modification. I have purchased two auxiliary tanks in the past for different motor homes. I went by and talked to the owner this morning. When I first asked he said that he would not do it because there were several reasons not to do it on a late model gas vehicle. After he realized that I had bought two tank installations from him and we talked for awhile he came around and said he would do it just for me. I also got him to agree to put together complete kits that he would ship out of California. I talked with Ross about "Get Lost 4x4" becoming the dealer for these kits.

Now some of the details and resolved problems. The first reason he said that he did not want to install the second tank is because of an interesting fact about newer vehicles. He told me that the Commander has a small air compressor that is controlled by the computer that compares the fuel level from the sensors to the pressure reading from the compressor that puts air in the tank. The computer compares the pressure to the amount of fuel in the tank. This is why we get the engine code if the fuel tank cap is not sealed. He said that this code does not hurt anything and can be erased by removing the ground cable from the battery. Even better he said that if I get the code he will install ball valves in the filler lines to eliminate the code. The details of the setup include a 20 to 25 gallon tank in the spare tire location, a skid plate under the gas tank, using the same filler for both tanks by installing a "Y" connector, installing a second fuel gauge, and a switch up front.

The way the system will work is to allow filling from a common filler, the back tank will have a sending unit for the second gauge and a pump controlled by the front switch to recirculate the fuel from the rear tank to the front tank. A second line between the two tank will allow the fuel to circulate back to the rear tank if the front tank is full to eliminate any possibility of pumping gas out of an overful tank. Each gauge would show the level of fuel in each tank. The combined fuel capacity would probably be between 37 and 42 gallons. He also agreed to let me take pictures of the install and all parts to post on the Forum. This fellow has several Cherokee's that are set up for off road use.

Sorry for the long post.

I now need to get my tire relocated out of the spare area and mounted on a tire carrier and give him a couple of days to install it.
 
#2 ·
Any idea how much it would cost and how "regular" people could get them installed?
 
#3 ·
I am going to wait unit it is completed so so that I can give accurate numbers, but he gave me some ballpark numbers that made me very comfortable with the cost. I would like to support Ross by waiting to see what could be done with the kit cost.

I do not think the installation would be very hard as long as these professionals put together every small part needed and use my commander to insure that all of the dimensions are right on. I would anticipate that they would have all the experience needed to create an exact fit solution.

After I have it installed and post all of the pictures you will be able to judge better for yourself.
 
#4 ·
Thanks for working that out, look forward to the pics!
 
#5 ·
I think the only way I'd put an Auxiliary Gas Tank where the spare tire is located is if I had a GetLost rear bumper or something equivalent. I could just imagine getting rear ended and causing mad choas.
 
#41 ·
Hi XK

I have a 110 litre Aux tank fitted in the spare area and the tyre relocated on a swing-a-way tyre carrier on my 07 3L CRD Commander. Have a look at the pics on my site. It has transport department engineering certification and is solid aluminium coated steel. being diesel then it's a lot safer I guess and the rear tyre carrier does gives it some protection.


XH
 
#6 ·
i'll have pictures of the spare tire carrier i'm building huey. i should have it finished today. we are powder coating it for him as well.

this set up is similar to phunky's. but ours comes standard with CB antenna mount, jerry can mount, license plate bracket, and frame extensions to keep it stable and not bouncing around, there is also a receiver hitch. you can order it off-set to one side like huey wants or you can have it centered on the back.
 
#7 ·
Copied this post to THIS THREAD. Please comment on Tire Carrier in linked thread and aux. gas tank in this thread. THX.
 
#8 ·
Wouldn't the tank be protected by the vehicle frame already? Also, don't be so sure that the dimensions and placement of holes and such are the same from vehicle to vehicle. I know there on some subtle, but important, body differences between the different models.
 
#9 ·
I would think so since the rear bumper is attached to the same cross member that the hitch and frame extensions are attached to. I wouldn't have any issues installing the tank since it'll have adequate protection.

Huey & Ross, let us know when the details are worked out and there's pricing available. Great job on this. :woot:
 
#10 ·
Yeah, hurry, so we can get them installed before gas prices sky-rocket again!
 
#12 ·
I am waiting on the rear tire carrier from Ross. The support brackets under the rear might be an issue when they install the second tank. I want to make sure so I am waiting for the carrier. I also have to go to Boulder for a few days so it might be next week before I have them do the install. They want it for a couple of days since it will be the prototype for a kit.
 
#14 ·
Update:

They are installing the tank next Wednesday and Thursday. I will either take pictures or have them take pictures of the install. They want it for two days to make sure of the fit and connections.

Film at eleven.
 
#15 ·
Update:

They started this morning at about 7:30. They are sure that it will be at least a 25 gallon tank. I am staying at a Hotel nearby because they will take all day and part of tommorow. They will put together a kit for "outside California" that will be complete. I anticipate that Ross will be able to add this to his product line. I asked them to take pictures and left my camera with them. The tank will have a skid plate under it. It may run off both tanks until the back tank get to a lower level and then I can pump the back tank into the front tank. They will each have gas guages. With an additional blitz can on the back I should have close to 50 gallons of fuel for exploring the back country.
 
#16 ·
Looking forward to seeing it soon.
 
#18 ·
Pricing yet? Rough estimate?
 
#19 ·
I am going to let Ross respond to the pricing issue. Tomorrow we should know what the kit full of parts will cost and Ross can decide how to proceed. I am just the facilitator for getting this kit available. This is kind of like a "Black Stealth" project where it is being done. The owner does not want to admit to installing it for me. The Kit is not illegal or anything and he is installing it on an out of state car, (my Commander) from Vermont.

New Update: He just called and said it is going very easily, no problems. Because of the connections between the tanks he does not need to split the fuel inlet line. He says the rear tank will fill first and then it will continue the fill the front tank. He is mounting the gauge to the right of my right knee under the dash and the switch will go in the console.

The tank will have a full skid plate. He said that he has taken many pictures.

The plan right now is to fill it in the morning about 9:00 AM and see how much it holds.
 
#20 ·
Man you got me on pins and needles with this install. Excited to see the results.
 
#21 ·
This might be something I get in the future. I'm always afraid of running out of gas on off road trips.
 
#22 ·
When I first came on the Forum there was a guy that was always complaining about the small gas tank. I cannot remember his name. I guess he gave up and quit.
 
#25 ·
When I first came on the Forum there was a guy that was always complaining about the small gas tank. I cannot remember his name. I guess he gave up and quit.
Mikey.
....
 
#23 ·
I put my complaining on a schedule so I don't over-do it. Small gas tank size comes back around in April.
 
#24 ·
Man, I'm going to have to have a garage sale to raise some money for all these great upgrades...spare tire carrier, aux gas tank, rock rail guards front hitch / wench mount. I wonder what my neighbor has in his garage and when he's leaving.:rofl:
 
#27 · (Edited)
A gallon of gasoline weighs anywhere from 5.93 to 6.42 lbs depending on temperature, type and blend. So if the aux tank is 25 gals that is about an additional 150 lbs (+or-) plus the weight of the empty tank and the skid plate.
 
#29 · (Edited)
I have not confirmed this yet, but I expect that I might get some really interesting results on the computer readout for both mileage and range. If the top half of the fuel tanks are linked as a common tank and the input for fuel tank level is comoing from the front tank sensor only, then the computer may calculate mileage and range on unreal numbers. I suspect that I will be able to photograph readings on the dash that will amaze you. They will not be real, but they might be interesting. I imaging that it might show double the MPG's and also inflated Miles to empty. Will see what happens, probably a learning curve on how to use this setup.

With this much gas onboard I might just have to ditch my JATO boosters.
 
#30 ·
I think you'll see a perpetually full tank and your readings will stay that way til its empty... just my opinion.
 
#65 ·
Polar,

You were right about that. That is what it is doing and no check engine light.
 
#32 · (Edited)
Nonetheless 700-800 mile range if you are getting 14-16 mpg, simply amazing! That will cover a one way trip to LV from the Bay Area on one tank!

I guess if the weight is going to be an issue one can always upgrade to the OME heavy duty rear springs that support a heavier constant load.

I am glad to hear that it would be armored! I would like to know for sure if it is baffled but the only thing that is a downer will be how the computer handles the extra fuel and calculations...crossing my fingers!
 
#34 ·
I am not worried about the computer calculations. I will still have two gauges to show me how much gas I have. Funny how we survived before we had a computer to tell us how many mile to empty we had. I am looking forward to a display that tells me I am getting 40 miles to the gallon, even if it is faulty information. Might be the source of a good practical joke on someone riding along. Maybe make up a story about having solar panels on the roof or something like a hydrogen boost system.
 
#33 ·
Another reason you have to make it to Colorado, everyone will want to see your modifications.