31 gallon tank conversion pictures

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boltbrain

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I took out my dual tanks and put this 75 Suburban tank in between the frame channels just behind the cab. A guy at the wrecking yard said I could put a 72 tank behind the seat but I can use that space for storage. The sending unit that was in the tank works fine with my gauge.
 

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EvilGenius

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Do you have a fleetside bed on this or a flatbed? Interested in what you did for filler neck routing
 

AuroraGirl

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I took out my dual tanks and put this 75 Suburban tank in between the frame channels just behind the cab. A guy at the wrecking yard said I could put a 72 tank behind the seat but I can use that space for storage. The sending unit that was in the tank works fine with my gauge.
Your axle , for sure, can NOT travel enough that it would be getting uncomfortably close, right? Id think since you have a center support that putting it there gives you the best safety but Id wonder if a load in bed and some torque wind up would pose a danger or something.
You wanted 1 tank im guessing, but if you could find onthats long and shaped like a right triangle almost you could get a lot of fuel to sit inboard the frame and never be at danger but it would be hard to find one youd have to get way more into it lol
 

boltbrain

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Do you have a fleetside bed on this or a flatbed? Interested in what you did for filler neck routing
It’s a wood framed flatbed. Yes I meant to mention that the stock box bed might be too low for this. Like I said in the “ can’t decide” thread, the tube on the tank clears the under side of my bed and goes level, like in the Suburban it came from, up to about 10” I guess from the last north spout. 10” away from the spout it turns up about 5 or so inches. My plan is to go back to the wrecker and get that spout that’s welded to the body. And put it inside a heavy steel tool box that has a door hinged at the bottom.
 

boltbrain

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Your axle , for sure, can NOT travel enough that it would be getting uncomfortably close, right? Id think since you have a center support that putting it there gives you the best safety but Id wonder if a load in bed and some torque wind up would pose a danger or something.
You wanted 1 tank im guessing, but if you could find onthats long and shaped like a right triangle almost you could get a lot of fuel to sit inboard the frame and never be at danger but it would be hard to find one youd have to get way more into it lol
Yes, this tank is way away from the axle. And about 6” above the driveshaft. Thanks for the heads up
 

AuroraGirl

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Yes, this tank is way away from the axle. And about 6” above the driveshaft. Thanks for the heads up
I see now you have what looks like a wood bed and your setup here stands far up :)
 

pduffyd

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Boltbrain
Ive done the same thing with my C20.
The 1986 tbi 31 gal seemed the right size, I put mine behind the rear axel, so I had to loose the spare tyre on my longbed



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I drilled out the rivets on the stifner between the rear spring perches and moved it to the rear of the frame. Then re-used the spare wheel hangar upside down to support the top of the tank, where the frame goes up, just behind the rear axel, then used 2x2 steel angle to use as a tank strap anchor upfront, just behind the brake flexi hose mount.
 
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boltbrain

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Nice. My 79 had no spare tire hanger. Would have grabbed the Z struts the tank on the 75 burb had hung from if I would have put it there. Might later. Where did you put the spare?
 

pduffyd

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The spare is gonna be hung on the drivers side, stepside fender, its noched for the spare. Im building this with a 58 apache body.
 

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