Auxillary Fuel Tank

[Quietman LBZ]

I have an 06 LBZ. I want to add a 60 gallon auxillary tank/toolbox in the bed. I want to utilize an electric solenoid, 3 line valve (supply, return & vent) to switch from the main tank to the auxillary tank. Also at the same time I want to install a gooseneck hitch. I will probably remove the truck bed for this project as I hate rolling around on a creeper and I know I will do a better job standing than laying. Please help me with the following so I know I am on track.

1) To my knowledge there is not a electric fuel pump in the main tank? The engine fuel pump draws the fuel forward? I have seen the articles and info on lift pumps and they seem to have good merit. Do you think that I should use a lift pump, especially in view of the fact that the auxillary tank is much higher up in elevation than the trucks main tank? Or, install a lift pump for use with the main tank and wire a double throw switch such that the lift pump only runs when the solenoid is sellected to the main tank and not the auxillary tank?

2) I plan to use some small hydraulic quick couplers on the auxillary tank so it can easily removed when desired. They will be properly sized so as not to impeed flow. I realize that there is a return line fuel cooler in front of the main tank. I intend to do the plumbing such that the cooler is always in the circuit regardless of which tank is selected. Other than proper routing of the lines and good workmanship, are there any other concerns that you might offer to keep me out of trouble.

3) I understand the supply & return line. Fuel tank filler caps have not been vented for a long time. Does the vent line return vapors forward to be delt with at some point in the engine fuel system? Could someone please explain this to me?

3) While I have gone to this much effort, are there other things I could/should do that I have not listed here? At this time I am especially satisified with the performance of the LBZ. I really don't plan many or any performance modifications at this point. I an extremely cautious with regards to the 5 year/100K miles warranty. The second week that I have the truck both door lock/ unlock zappers died. I went to the dealer and spoke with the diesel mechanic. He told me that if you change anything (air intake, exhaust, etc.) the engine will pull codes and Chevy will void the warranty. I am sure that this varies from dealer to dealer but I am going to be cautious non the less. Please advise.

Thanks in advance!

Jim
Houston, Texas

[More Power]

[COLOR=black][FONT=Verdana]Duramax equipped trucks don

[jcummins]

Don't do it. Transfer the fuel from the aux tank to the main tank. I had that setup, and I had fuel pickup problems with the aux tank. Then, west of Memphis on a holiday weekend, the multi line value failed. The return portion switched....the supply did not. Diesel all over the place. I had enough hoses/tools with me to change over the lines to get me going, but had to craw around in diesel fuel to get it done along side the interstate. Much happier with a simpler transfer process.

[cowboywildbill]

We went with a transferflow 56 gallon replacement tank on our 02. It really held a little more than that aprox 60 gallons. It was easy to do and was trouble free, and you don't have a tank in your bed.

[FBJR]

I have looked at the transfer flow tanks too but the cost keeps me away. To bad there is not a simple add on that would go in that big space in front of the cross member down there.

I thought about adding a small tank in the bed over the wheel well to the front so I could still use the whole bed. Trouble is it would only hold about 20 gallons. That would be enough and a siphon feed to the main tank would be easy too. It would just cost to much for the tank since it would be a total fab job. Since I have a shell I figure it could be filled from the rear using a stock filler neck bolted on and just reach in.

If only GM would have made the tank to be around 35 gallons I would be happy. There is so much wasted space under there :mad:

FB

[Quietman LBZ]

Thanks for the response. After doing a little more homework I realize that I missunderstood the 3 hoses coming off of the main tank sender. I thought that the diesel had a vent/vapor return like a gas burner. It does not. The 5/8vent hose goes up to the tank filler neck. So I only have to be concerned with the supply and return lines. For the auxillary tank I will vent it with currly-Q or something. I am still going to use a lift pump. I will probably get it from Kennedy as he has some neat stuff. I like the wire harness setup he has for the lift pump. I will also add another diesel filter after the tanks and prior to the lift pump.

Thanks,

Jim