Well after a long layoff I'm finally back at my build.
I have finished most of my cab body work and have turned to installing my gas tank under the bed. I was wondering if anyone has successfully ran the gas filler tube thru the back bed crossmember. Looking at my tank set up and having almost 7" from the tank to the bed, I'm thinking that should work.
Any ideas/concerns based on these pics?

 

The only thing I would ad is that straight out the back is how Ford ran the filler tube in the original setup for that tank in the Mustang. And there's a reason they don't do that anymore; it isn't the safest of setups. I'm sure it would work with the proper boxing and strengthening of the rear box crossmember, 'cause you'll be putting a pretty big hole in it. It may also be inconvenient to fill there under the tailgate and around a bumper, if you intend to run one. Just some things to think about.

 

Hey *****,
Not sure I fully understand your question but here is a picture of
our 1950 F1 with the "in the bed" filler option. We used a 1970 22 gallon Mustang tank. I hope that helps.

Ben in Austin

 

I used the same tank (22 gal) on my 55 and ran it up through the bed the same way Ben did.

 

Thanks for the input , I was thinking of having it in the bed initially, they look great but thought it would be nicer to have it where one wouldn't have to drag the hose over the tailgate or move stuff if box was full.
Not sure of the danger having it out the back as the early Mustangs had it, although I won't have a back bumper. I could reinforce the crossmember too if need be, not sure how that will make it any safer.
I was thinking of installing a round or oval fuel door through the back crossmember in my roll pan, centered just below the tail gate. This way I could use a venting gas cap too fixing the other issue I need to deal with.

 

The danger of having the filler neck straight out the back is that it's the first line of defense in the event of a rear end collision. Especially without a rear bumper, if the truck gets hit from behind, the filler neck gets knocked off the tank and gas can splash/spill from the 3" hole in the top. Long before the Pinto explosion debacle in the 70's, gas tank issues were haunting Ford from all of their compact and intermediate models, which all shared that tank fill design in the 60's. They just didn't get the press that the Pinto thing did, since the early 70's was about the time our country started becoming more litigious and consumer protection efforts became more mainstream.
Ford wasn't the only one, either. GM had their issues with the filler behind the license plate. It wasn't as quite as bad, though, since those big GM barges had huge bumpers in the back to somewhat protect the tank and they didn't have the rubber hose connection between the neck and tank. That was Ford's downfall with the Mustangs, Falcons, etc., plus they only had that little ribbon of decorative sheet metal they called a bumper.

 

If I did go that way I would install gusset supports on to the last frame crossmember, which I moved from over top of the tank, making the frame all one piece and there would also be a rubber hose connecting the tank to the filler spout taking up some impact. The box crossmember is only to hold the box together.
In the event I get hit that hard not sure if any rear mounted tank would survive but still better than sitting on one or having it right behind you.

 

Hey *****,
I don't think sitting with the gas tank is a better alternative.
Just to be "safe" the guys putting my bed back together put a little
solid steel around the tank.

Ben in Austin

 

Not telling you how to build your truck, but just wanted to be clear that the rubber hose connection between the filler neck and the tank was a big part of the problem. Because the neck was the first thing to be hit, the lack of a solid connection allowed the neck to become disconnected which opened the hole allowing the fuel to spill in a collision, even if the collision wasn't hard enough to damage the tank. It is not an impact absorber. Just a couple of inches impact is enough to have the neck become dislodged. This is why all automakers have gone to a side fill 40 years ago.

Just a little FYI history lesson. You asked for our concerns and observations, I'm just sharing mine.

 

i have the `70 mustang tank in my truck for better acess to the tank filler i made my tailgate open sideways, this way i won`t have to drape a hose over the tailgate and being short, its kinda hard to get to the filler.

 

Wayne, I appreciate all your input and safety is a factor....so thanks!
Gil, if I had your ability I might think of a side swinging tailgate but I don't.
My tailgate will probably be bolted shut so thats why I'm thinking of having it out the back but could end up inside too!
Ben, never wanted the tank on the inside the cab, that makes no sense too me there. But reinforcing the tank area maybe what I will end up going to.
Need to think this all thru as I put my box together.
Thanks for all your inputs it is/was sought for.

 

Well had a good day today mocking up my new box. It required only slight mods to make it fit and to get it square. Only thing that needs to be done is to line up some of the board bolt holes in the front cross member, not sure why they seem to be off on the edges. (A whole hole out??)




Tomorrow I should have the running boards and rear fenders mocked up along with my roll pan. I maybe dreaming but thats the plan.

 

Not a good day today, I had to redo the box as someone put the sides on the wrong side of the front panel.(reason for holes not lining up). Well after that I got the box all nice and square and bolt into positon. Hung both back fenders that went good but when I slide the running boards into position I notice on the passenger side that the running board was about 1 1/2 lower than it needed to be to run into the rear fender. Assumption here that the out rigger brackets must be spread. Same thing on drivers, now that is starting to seem funny???????? Also running board is tight on drivers between front and rear fenders.
Not sure what is not square with the frame. When the cab was mounted check many times off the frame for squareness. Front sheet metal worked out good. My thoughts are the box needs to be tweeked to square with frame?
Any ideas here would be really appreciated especially the reason for running board height not right? Spacers missing/ are there any?

 

I think I have found my problem in that the box is out by 1/4" for squareness to the frame. That should even out the running board issue for length. My bigger problem is the rear most bracket for the running board seems to be too low for the alignment into the rear fender. When I cleaned up my frame I removed the brackets for the running boards because some were rusted badly and replaced them with others that came off another frame and bolted them in with grade 8 bolts to what I thought was the correct mounting holes.(not much to choose from as there are only 4 holes)
I'm thinking mine maybe sprung or possible the wrong ones if there is a difference between front and rear brackets?

What I could use is a measurement from level with the bottom of the frame to the top of each RB bracket. Mine measure 4" at the rear bracket and 3.5" on the front bracket.

 

And IIRC, my 73 Monte Carlo with it's filler tube behind the plate took gas slowly at best and would burp a lot.