Dual tank on a short bed

[Zach86]

I have a 1986 Crew Cab short bed. When I bought it it only had the drivers side 16 gallon tank. Am I able to put another 16 gallon tank on the passenger side? I have a fuel door but no tank. Thank you.

 

[Blue Ox]

Yes you can. You'll need the tank (obviously) and the brackets and straps, but since you've already got the fuel door it's a bolt-on retrofit. I'm guessing a replacement bed or side panel, or was it originally a dual tank and somebody removed it? You'll probably need the selector valve and switch too if it's not already there.

 

[80BrownK10]

Yep I don't have a crew cab but I have a short bed k10 with dual tanks

 

[Zach86]

Awesome thanks. I bought it salvaged. It was a long bed but the rear end was smashed. So they chopped it and put the short bed on. Will this require a fuel pump with dual inlets? Reason I ask is I replaced the old fuel pump and it had an extra inlet plugged. I didn’t get a new one with the extra inlet.

 

[Scott91370]

Your current fuel pump will work but are you sure that is a plugged inlet and not a return line? By the passenger's side tank, bolted to the frame, there will be a gizmo that does all the switching of which tank the fuel is pulled from and returned to. If that's not there it may be a somewhat costly install.
From here https://www.lmctruck.com/1973-87-ch...cc-1973-87-side-mount-gas-tank-and-components you'd need parts 17 18 to start. The passenger's side tank would need to have the sending unit parts and wiring. You'd also need the in cab switch. And I am sure there are other parts I am missing.

 

[80BrownK10]

Some fuel pumps have three ports, some two, either works on these trucks. I'm thinking the other has to do with a return somehow

 

[TrybalRage]

I'm in the middle of tearing my system out... I have a LWB with dual 16 gallon tanks and I'm going with a single 20 gallon.

You'll need:

• Tank (same tank # as drivers side)
• Passenger side sending unit
• Straps/bolts/hardware
• Fill and vent tubing, along with the filler neck with flap
• Fuel tank switching unit/motor. This takes the send/return/vent lines from both tanks and then provides the outputs to your motor/pump and charcoal canister
• Wiring harness - including switch in dash that gets power from fuse block, two wires (green) that go to the switching unit, plus a ground. At the tank end, there's also two wires that go from the 6-wire plug to the sending unit on each tank and the switching unit connects them to the main gauge wire (pink) that you probably already have running back to your tank.
• All the fuel/vent lines of your choosing

I have some links that explain the wiring but don't know if I'm allowed to link to another forum. Google search "c10 dual tank theory of operation".