Relocated fuel tank question

[Kiwi]

I have a 1971 C-10 with the traditional fuel tank mounted just behind the front seat. I would like to remove the stock tank and replace it with some type of under-bed fuel tank.

Unfortunately I can not use the most common type of aftermarket fuel tank that mounts at the rear of the bed in-between the frame rails as:

1. I already have an aftermarket trailer hitch that hides in that area.

2. In the summers I install a vintage Alaskan pop-up camper in the bed which would make it nearly impossible to fill up the fuel tank (as the gas cap is usually on top of the bed or mounted in an area of the bed side).

+++++

My dad bought new a 1971 Cheyenne that had an optional fuel tank located on the underside of the front left portion of the bed (just rearward of the driver). I don't remember if the tank was installed from the factory or installed by the dealer … but it definitely wasn't installed after leaving the dealership.

Questions:

1. Does anyone know if this tank was factory or dealer installed?
2. What was the size (in gallons) of the auxiliary fuel tank?
3. Does anyone reproduce the tank, mounting straps, and fuel filler hose assembly?
4. Does anyone reproduce a similar tank that is larger capacity than the original side tank?

[Hawghauler]

You could just put in a saddle tank and mount the filler tube in the fender well. This is how the factory mounted them. The ones you see with the doors in the bed sides are add on tanks installed by dealerships. I think the saddles also carry more fuel than the cab tank.

[hugger6933]

There was one of those very tanks on here last week for sale I think. Jim

[67swb72klb]

here is the thread http://67-72chevytrucks.com/vboard/s...d.php?t=612928

there is a craigs list ad for one for sale good luck

[SS Tim]

While you could install a saddle tank or even a pair (~19 gal each) they were not intended to replace the factory tank and most but the RPO NL2 tank or GM acccessory tanks do not feature senders for the fuel gauge. Not to mention saddle tanks were not EEC compliant as was required on 1/2 ton trucks.
Camper, even a 8' Alaskan weighs about 1700lb wetIIRC. Might want to consider how much your truck actually weighs. Suggest weighing the front and rear axles all loaded uo to see where you are at. An overloaded semi-floating axle is not a good thing. As a final note moving the tank rearward from the cab will increase rear axle weight where you migh not have much if any margin. The General Information section of the factory service manual has good loading information as does the drivers handbook (owners manual).

[brad_man_72]

I have an underbed tank (fuelcellguy) and a trailer hitch on my swb.
Fuel door on the outside of the bed sourced from a 90s chevy truck.

[Kiwi]

Originally Posted by 67swb72klb

here is the thread http://67-72chevytrucks.com/vboard/s...d.php?t=612928

That is an interesting thread with lots of good info.

There are numerous references to that saddle tank being a 1972 only option … however, my dad's 1971 Cheyenne has the exact same saddle tank, filler neck, in-cab tank choosing valve (mounted on the floor), and a switch that would allow viewing the fuel levels in the two different tanks. Thus, it can't be a 1972-only option. (Note: my dad bought the truck new and has owned it ever since. Thus, it's not like someone else installed it.)

In other news, does any company offer a reproduction of this factory saddle tank setup?

[SS Tim]

On the NL2 I agree that it was offered earlier. The Custom Camper brochure lists it and 71 painted trucks. Strongly suspect it was a mid 71 release. Still trying to nail that down. Do you have the VIN or production date of your dad's truck?

As far as aftermaket goes I haven't seen any but a member did have and aluminum tank welded up a couple of years ago.

[Kiwi]

Originally Posted by SS Tim

Strongly suspect it was a mid 71 release. Still trying to nail that down. Do you have the VIN or production date of your dad's truck?

I just spoke with my dad and he confirmed that he took delivery of the truck in July of 1971. It was a custom order rather than just picking a truck from ones on the lot. The truck is a 3/4 ton with multi-leaf rear springs, long bed, fleet side, 2WD/RWD, 16.5-inch steel wheels, 350 V-8 with QuadraJet 4V, 3-speed manual (on the column), A/C, P/S, P/B, AM/FM, saddle tank (with internal sending unit), and Cheyenne trim package.

My dad (who still owns the truck to this day) just looked at the VIN tag and he said that in addition to the VIN info (see below) that the tag also said 6/71, indicating that it was built in June of 1971 … which is very late in the run.

Here is the first part of the VIN info (but missing the last two numbers of the VIN for privacy).

CE241S6730

If I am deciphering correctly, the VIN equates to:
C = 2WD
E = V-8 engine
2 = 3/4 ton
4 = pick-up
1 = 1971
S = St. Louis built

[SS Tim]

Wow, last of the last 71s! Thanks for sharing.
Does he have a build sheet by chance?
Now of course we need a picture of that truck and your dad together!

[brad_man_72]

Swamp rat wanted to see pics of my underbed tank and hidden hitch.
From behind. Cell is hidden by the not so hidden hitch brackets.
Passenger side. Cell flange to the outside, hitch flange to the inside.
Rear of tank. From L to R license plate bracket, hitch, fuel cell.
Filler from 90s chevy truck.

[swamp rat]

Originally Posted by brad_man_72

Swamp rat wanted to see pics of my underbed tank and hidden hitch.
From behind. Cell is hidden by the not so hidden hitch brackets.
Passenger side. Cell flange to the outside, hitch flange to the inside.
Rear of tank. From L to R license plate bracket, hitch, fuel cell.
Filler from 90s chevy truck.

Thanks for posting this, so it looks like the tank flange is sandwiched between the frame rail and hitch brackets correct?

[brad_man_72]

Originally Posted by swamp rat

Thanks for posting this, so it looks like the tank flange is sandwiched between the frame rail and hitch brackets correct?

That is correct. Its good to have a couple extra bolts in the tank so you can install the tank before the hitch. Or when removing you don't have to catch a hitch and the tank at the same time.

Is it secure and reliable? Haven't lost a trailer yet.