The Stovebolt Site Forums The Shop Area General Truck Talk Out of cab fuel tanks (Task Force installation)

A new tank isn't a performance option, or part of the engine, and outside the cab it isn't an interior part. Soooo I am putting this in GTT for lack of a compelling reason for it to be anywhere else. If someone has a strong feeling about somewhere else it should go, let's hear why.

Anyway, the tank in my 58 is mostly rusted through and needs replacement. I am not really worried about the safety aspect that a lot of people bring up for those tanks, but I like having space behind the seat for tools and emergency gear.

I have been looking at various options to move the tank out, but even the "cheap" ones are $500+. If you want one with a side fill instead of a bed fill the price goes up to the $700 range, plus senders and accessories. Most of the available underbed tanks are also only 12-15 gallons and I explicitly did not want to lose capacity.

What I found is that Tanks Inc. makes a 69-72 Blazer tank that looked like it would fit for $329. It is an 18 gallon tank with a side fill that is fully baffled and has an integrated return bucket if someone wanted to use it with EFI.

I picked one up and it fits like it was made for the truck. I set it up where the passenger side flange slides up into the frame channel, then the driver side is lifted up and both sides bolt through the existing spare tire lift holes.

There is ~1" of space from the top of the tank to the bottom of the bed supports, so the fact that the sender and pickup tubes are below one of the supports is not an issue.

The tube for the filler neck fits nicely between the top of the frame and the bottom of the wood. In the picture below, I have the neck turned down for convenience. My short term plan is to just turn it up and have it come through the bed until I redo the wood. Once I am ready to work on the bed, I will make a fender door/box for it.

Overall I am *quite* pleased with this. It is basically flush with the bottoms of the fenders and the flanges are wide enough that I can still reach in from the back to tighten the bolts on the bumper supports.

I am hoping to get it drilled for the mounting holes and permanently mounted tomorrow.

Tank link: Tanks Inc Blazer Tank

Jason, The post topic fits in GTT just fine. As it is primarily geared toward using this tank in Task Force pickups, maybe revise the title a bit to be a little more specific on your application? That will provide more detail about the post for future Bolters searching for what others have already done.

On that note, I read several older posts on tank relocations and some indicated this particular tank has also been used in relocating AD series pickup tanks from cab to under bed.

Looking forward to seeing/reading more on your project.

I have read a decent amount on TF conversions and have not seen (or at least noticed) this tank mentioned for them before.

My plan was to make a fuel door in the driver fender, but I am toying with the idea of hooking it up to the stock filler. There was a previous thread (that I can't find at the moment) where someone connected the stock filler to (fiero?) tanks under the bed.

This is a 1.5" filler. The stock one is 1.375", but I should be able to make an adapter for that.

Looks like this is the thread I was remembering.

I need to take some more measurements since his don't match mine. Interesting.

I will keep y'all posted.

Thanks for updating the title Jason.

Just a side note, this tank works great for 3100 (1/2 ton) trucks but not for 3600 (3/4 ton) trucks. The rear frame spacing being different between the two. I also did a tank relocation using a Tanks Inc. for my 3600 but I did loose capacity.

Is it possible to leave the in cab filler neck and use fuel filler hose to run to the tank through the cab floor?

I am trying to figure that out. The potential issue I see is that the vent comes over the frame rail with the fill tube. Routing it to the cab filler will require letting it dip down under the bed supports. That gives the potential for trapping liquid in the vent side and causing issues with fill rate.

What about out the back of the cab just above the floor (between the bed front and cab back)? Perhaps a solid metal or PVC bend could be used there.

I think Mike B used this or a similar tank on his wife’s TF and used a side door. I believe he told me he ran some plumbing down the passenger side to accommodate filling.

Victor, I sent Mike B an email on this. He'll respond (with pix I'm sure) as soon as he is able. Good call on this.

Excellent point and great info on the distinction between 1/2 and 3/4 ton AD trucks. Thanks for providing it!

This might inspire something. Its on a S10 chassis but if you notice, he did use the filler location in the cab & the factory S10 tank in the chassis.
This link is below, there's more pics there too.....

https://bringatrailer.com/listing/1951-chevrolet-3100-pickup-2/#comments-anchor

Amazon sells the tanks for $120 ( w/ free shipping)
Comes with 20 gallon capacity. Get an exhaust shop to bend a stainless steel exaught pipe ( or 2) & use the factory fill location.

For Dana's '56 3100 I used a Panel/Suburban tank that mounts between the passenger side frame rail and the driveshaft. I really didn't want to use a in-bed filler as we knew we were going to add a tonneau cover to secure our luggage when we travel and we didn't want the luggage to smell like gas if it dripped while filling. The Suburban tank also allowed us to retain the spare tire in it's factory location, a must for long distance travel. A bonus is that this tank is a direct bolt is as the frames are all made the same. The only down side is the tank is only 15 gallons.

For the filler door I used Tanks Inc Filler Door FFD-A and cut it into the rear passenger fender just behind the tire. It basically took (2) fuel rated 90* rubber hoses and a straight piece of thin wall galvanized pipe to plumb it out. The only tricky thing was getting the vent done, I connected copper tubing to the factory tank vent and ran it inside the fender well to the underside of the top of the fender then bent a U-turn and dropped it down to the bottom of the fender so if it puked any gas it would just drip on the ground and not on the fender or frame.

https://www.tanksinc.com/index.cfm/...=466/category_id=-1/mode=prod/prd466.htm

Mike B

Thanks Mike. I looked at that one as well, but explicitly did not want to lose any fuel capacity from the stock 18 gallon tank.

I like how your door came out.

Are you positive the stock behind the seat tank on a 58 is 18 gallons?

Gents, Just a technical note to help the conversation move along. Original Chevrolet resource info I found for 1958 Chevrolet Pickups lists all 3100-3800's came equipped with a 17-1/2 gal capacity fuel tank in cab. The 18 gal capacity indicator comes from the descriptions given to reproduction replacement fuel tanks by most every vendor such as the Tanks Inc Model TM55B.

You can see all the fuel tank capacities in this 1958 Chevrolet Truck Full Line pamphlet. Anyhow, moving along...

I completely understand not wanting a smaller tank, in my case I didn't want to lose the spare.

As a side note they did have a 21 gallon in-cab tank available for the bigger TF trucks.

Mike B

My plan is to build a spare carrier to go in front of the fender in the bed.

The bigger inside tank is interesting. I will have to look at those.

I don't believe anyone is reproducing these 21 gallon tanks, you have get them from a donor truck...you'll need the filler neck as well as they are different than the 17 gallon neck.

Mike B

I needed to remove the interior tank to get the seat out because someone had welded it in. I found this under the tank, which makes me fairly confident that whoever welded the seat in did it with the tank in place because the seat is from a 90s F*ord...

Braver than me, I guess.

$5 each for shocks. Sign me up!

I'll do the shocks and take them up on free tire storage!