Rear mounted fuel tank

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lobie
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Rear mounted fuel tank

Post by lobie »

I had to take the stock fuel tank out due to my drivetrain swap. The tank and tc were interfering with each other. I have read about people using 90's model suburban fuel tanks in place of the spare tire. Since I can't put a 35" spare tire in that location I'm gonna put the fuel tank there. Also going to put duel batteries back there.

After doing some measuring it seems the suburban tanks are deep (13.125") and may hang down too low. It is also pretty long (33.5") and appear it may get close to the rear diff at full compression.

The last issue is locating batteries back there. So after searching through oem catalogs I found a tank from a 91 ford e350 van that should work. The dimensions are as follows: w x l x d -> 33.5 x 23.5 x 11.125. (22 gallons). It's not the 30+ gallons I wanted but what I do get out of this configuration is some better weight balance with the fuel tank and batteries behind the rear wheels since the cummins is much heavier than the 360.

Has anyone got any pics of the fuel tank setup in the rear? Would like to see how the suburban tank (or other tank) worked out.
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Tad
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Re: Rear mounted fuel tank

Post by Tad »

Sounds pretty similar to my S10 tank, 22 gal, about 20 of that is useable.
I'll find the link to the pic's when I get back to the house, no access to that site from work.

EDIT:
http://members.cox.net/pmountsoa/pmountsoaindex.html
Got into the other site and found it.
Tank pic's start on about Day 16.
It has a skid plate welded to the lower straps now that has taken quite a few hits.
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Re: Rear mounted fuel tank

Post by lobie »

Thanks. That's what I was looking for. What year s10 was that out of. I like the unistrut idea.
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Re: Rear mounted fuel tank

Post by Tad »

Early '90's S10 Blazer.
I pulled the in-tank FI pump out and extended the pick-up tube down.
It was getting parted out here at work so I got that and the front seats.
You could probably get something bigger into your newer rig, the older pre-'74 rigs are limited by the placement of that round rear x-member.
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Re: Rear mounted fuel tank

Post by lobie »

The other thing in the way in the back are 2 diagonal braces for the hitch receiver. They go from the middle (at the receiver) and at a 45 deg angle out to the out side of the frame.

Looking at yours, you dont have that brace. Maybe I can do away with since I'm gonna make some heavy duty bumpers. That will free up about 8-12" in the rear.

It's kinda hard to explain. I'll see if I can snap some pics and post.
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Re: Rear mounted fuel tank

Post by Stuka »

Are you referring to the small braces in the corners, or some larger after market brace that came with the hitch? If its a big brace thats part of the hitch, and you aren't going to be towing, pull em off. The small ones in the corners help tie the rear cross member into the frame.
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Re: Rear mounted fuel tank

Post by lobie »

Stuka wrote:Are you referring to the small braces in the corners, or some larger after market brace that came with the hitch? If its a big brace thats part of the hitch, and you aren't going to be towing, pull em off. The small ones in the corners help tie the rear cross member into the frame.
I will use it to tow boat or camper.

This is a pic of Tad's and the way the brace is on mine I wouldn't be able to mount my tank like his.
http://members.cox.net/pmountsoa/Day16/ ... arance.JPG
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Re: Rear mounted fuel tank

Post by Stuka »

Ahh ok. Well if you are going with a custom bumper, just be sure to have some frame tie-in's. I have this on my bumpers (That Tad build for me) which ties the bumper into the main frame rails. Don't rely on that rear cross member alone.
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Re: Rear mounted fuel tank

Post by lobie »

Thanks. I will defiantly tie it into the frame rails. Taking the braces out should allow me to fit a 30 gallon tank.
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Re: Rear mounted fuel tank

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lobie wrote:Thanks. I will defiantly tie it into the frame rails. Taking the braces out should allow me to fit a 30 gallon tank.
I'll find some pic's of mine for you also.
(Actually they are way at the end of my link above)
I placed all my frame tie-in's on the outside of the frame and turned the rear x-member into a mini I-beam with a reciever. All bolted in place so it can be removed
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Re: Rear mounted fuel tank

Post by Jeffsj »

If it helps, here are some pics of my setup from a 97 2 door blazer (21gal.)

Image

Image

Image

Image

Image

Image

In the second pic you can see where I had to add a cross member for a rear attachment point for the straps. You can also see where I added 2 pieces of 2" c-channel to shim the tank down enough to give the pump and fittings room. Hope this helps.
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Re: Rear mounted fuel tank

Post by lobie »

Thanks. Looks like I'm going to go with an early 90's s10 blazer like above and Tad's. The depth is just over 10" so it will give good ground clearance.
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Re: Rear mounted fuel tank

Post by lobie »

Stuka wrote:Are you referring to the small braces in the corners, or some larger after market brace that came with the hitch? If its a big brace thats part of the hitch, and you aren't going to be towing, pull em off. The small ones in the corners help tie the rear cross member into the frame.

Finally got a pic of the braces I was talking about. They can stay in and aren't in the way with the 90's s10 blazer tank. Thanks for all the pics. The tank works good and still have good ground clearance. Should get about 300+ miles on a tank of fuel.

Image

Image

Image
77 Wagoneer | 6.0 | TH400 | NP205 | Sterling 10.5 | Dana 60
07 6.7 Cummins 2500 4wd

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Re: Rear mounted fuel tank

Post by lobie »

Installed.

Image

Image

Image

Image
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Re: Rear mounted fuel tank

Post by carnuck »

I have an XJ tank planned for mine
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Re: Rear mounted fuel tank

Post by wewillsurvive »

carnuck wrote:I have an XJ tank planned for mine
Did you ever get the XJ tank in Carnuck? Do you have dimensions? What year are you using?
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Re: Rear mounted fuel tank

Post by carnuck »

I just snagged a tank from an '84-86 XJ (later ones have the fuel pump in them) With the jump in gas prices, I'm going to LPG which is half the price here. I'll run carb style with an HEI dist till I can afford the LPG injector system.
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Re: Rear mounted fuel tank

Post by wewillsurvive »

Looing into this, what do you do if you are running a carb?
1972 Dodge Demon with a 451" stroker Big Block
1986 Jeep Grand Wagoneer AMC 360" AKA Golddigger- SOLD
2003 Dodge Crewcab 2500 Cummins longbed 4x4
2011 Jeep Grand Cherokee V-6 full time 4x4


Alternators, winches, 4x4, guns all have the same issue if you don't have any knowledge of them usually bad things will happen. Serehill
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Re: Rear mounted fuel tank

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wewillsurvive wrote:Looing into this, what do you do if you are running a carb?
I simply pulled the in tank pump assembly (it's connected to the sending unit), cut the pump off and extended the pickup tube down to about 1/2" off the bottom of the tank (section of fuel line, 2 hose clamps, short section of 3/8" ID AL tube).
I did go back in to check it last fall when I thought I was having some fuel delivery issues but it was fine and has been fine for over 9 years that way.
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Re: Rear mounted fuel tank

Post by wewillsurvive »

Thanks Tad
1972 Dodge Demon with a 451" stroker Big Block
1986 Jeep Grand Wagoneer AMC 360" AKA Golddigger- SOLD
2003 Dodge Crewcab 2500 Cummins longbed 4x4
2011 Jeep Grand Cherokee V-6 full time 4x4


Alternators, winches, 4x4, guns all have the same issue if you don't have any knowledge of them usually bad things will happen. Serehill
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