Dual tank Question . .

[fryguy]

. . .Hey guys, been a while since I posted. Just recovering from the recent flood here in SE PA about 3 weeks ago. My house and garage were under 8 ft of water. Life is starting to get a little back on track.

Right before the flood, I purchased a 72 longbed Cheyenne 1/2 ton for parts. The truck actually was in better shape that what the pics showed. The front of the hood is crinkled and the grille and bumper are creased where the PO ran into a fence post. The question I have is that looking underneath it looks as though there is another fuel tank on the front right side underneath the bed right before the cab. Its square and black and looks like it could hold between 10-15 gallons(??) There is no other filler neck other than the stock filler on the left side of the cab behind the drivers door. Does sound familiar to anyone? Or is this possibly an home made job. I don't see any obvious fuel lines to the black box. I do follow the fuel lines from under the cab from the stock tank and it looks like one line travels along the frame to the back of the truck. Could there have been a tank at the back and it was relocated? I checked the RPO tag on the glovebox door and it doesn't mention anything about dual tanks. Its a 350cid Cheyenne 1/2 ton. Should I look for a specific code?

Also, it has a G80 rear which stands for Standard Locking rear. Does anyone know the Standard Locking rear ratio, lol? Was there a standard ratio or do they all need to be pulled and counted? Thanks for taking the time to read this.


Fryguy

[dave666693]

I have similar tanks and was told they were a dealer installed option. Mine have filler doors above each on the outside of the bed. Do you have a valve on the cab floor by the drivers seat to switch tanks?

[Longhorn Man]

you mentioned the small block power... if it is a 4 speed tranny, or an automatic, then 3.07 was standard, if a 3 speed manual was there originally (indicated by nothing specified on the SPID label) then a 3.73 was standard.

[fryguy]

Thanks for taking the time to reply. In regards to the dual tanks. I didn't check under the drivers side yet, but I will look. I cannot locate the second filler neck but I noticed there is a patch panel on the right side of the bed, right where the fuel tank is. I didn't notice it at first underneath the 200 layers of black paint, lol I was wondering if the second filler neck was removed or shaved off.

Taking the second fuel tank into consideration, can I remove the behind the seat tank and just use the second under bed mount as the primary tank?


LM, the tranny is an auto th400. That would tend to lead in thinking the rear is a 3.07 ratio posi? That kinda sucks. Like I said, I am using this new parts truck to improve my 70 c10. Right now, I have posi 4.11 gears and and powerglide tranny. So gas milage kinda sucks. I was hoping the rear ratio was a 3.73. Well, i guess you can't have everything.


I will be parting this truck out so I will be posting an add in the classifieds.


Fryguy

[Stocker]

Originally Posted by fryguy

Taking the second fuel tank into consideration, can I remove the behind the seat tank and just use the second under bed mount as the primary tank?

It should work, but you won't be able to go far on ~15 gallons....

[special-K]

Are you sure it`s a gas tank and not a tool & stowage compartment that`s been covered over due to their notorious rust problems?Is the lower/outer edge fastened with several screws to the body?Do you have the option sheet on the glovebox door?The fuel line you see running to the back may be part of the vent-system.`72 trucks had them run up in the cab roof pillar,but maybe was relocated.Just a few hunches.

[fryguy]

I checked the drivers side under the seat and there is no valve. I did check the RPO again it does say that is has an auxilliary tool box. Now it does make sense. It must have rusted out and a patch panel was put over it. Thanks for clearing that up.


Fryguy