I want to put an additional fuel tank in my '06 2500hd crew cab short bed and rather than replacing the OEM tank, I was thinking about putting a larger additional one in the bed. I'm concerned because I also want to put a camper top over the bed. Does anyone have any experience doing this? If I used one of the kits to direct the fill cap to the outside of the top, do you think I would have problems with my entire bed smelling of fuel? Does anyone foresee any safety hazards? Much thanks,
CAL

I can tell you that I have seen one with the filler hose going through the camper shell and it looked good. I have in bed tank, but no camper shell and I when it gets hot outside I can smell the diesel going out the vent in the back of my truck. If you were to move the vent outside the bed it would be better. If I were you, I would look to get the bigger replacement tank. It just seems easier for your situation.

thanks for the reply. I'm going back and forth. The possibility of adding 50-70 gallons to my stock tank is pretty attractive, but the undercarriage tanks max at 52 gallons total as opposed to a possible 100gallons. One concern I've been trying to come to terms with about replacing the OEM tank is that I've had people tell me that they've had problems with the fuel gauge floater when they replace the OEM tank, in that the calibration has actually left them empty and stranded when they didn't know that they needed to reprime the pump. Once they figured that out they occassionally still end up with much less fuel than they had thought, but if it stalls, they know they need to reprime the pump and they can switch to their in bed tank. Now, having read some of the discussions, I'm also questioning the transferflow steel vs other brands made of plastic. Or, just redirecting the vent through the wheel bed as you mentioned. I'll keep you posted, but any and all input is very much appreciated.
CAL

i guess the transferflow tanks are aluminum and most likely the rust issues is less of a problem than in the ones people have written about in other threads?

From the Transfer Flow website:

Made from 12 and 14-gauge aluminized steel
Mounts inside frame rails
Tanks are baffled to reduce fuel sloshing
Available for gas and diesel pickups
45 & 56 gallon tanks hang down one inch below the lowest part of the frame rail
Complete fuel tank system
Fuel tanks available for trucks with 6.5 or 8 foot beds
Optional fast-fill fillneck kit available
3 year/36000 mile warranty
Meets all federal and state emissions regulations

http://www.transferflow.com/gm_tanks_0.html

I want to put an additional fuel tank in my '06 2500hd crew cab short bed and rather than replacing the OEM tank, I was thinking about putting a larger additional one in the bed. I'm concerned because I also want to put a camper top over the bed. Does anyone have any experience doing this? If I used one of the kits to direct the fill cap to the outside of the top, do you think I would have problems with my entire bed smelling of fuel? Does anyone foresee any safety hazards? Much thanks,
CAL

Where do you live? I have a brand new Diamond plate one for sale? It is a tank tool box combo. Tank is shaped like an L but the tool box makes it a square. Never used. I live in Upper Michigan. Paid $800, I will take $500.

I've had an American Tank www.auxtank.com 40 gallon aux in the bed of my truck since Dec 2001. I had it piped through my Century Ultra cap until I took it off for a Fold-a-Cover last year. I installed a racing roll-over plate and the through-the-cap filler when I first installed the tank. Pictures are in my garage.

I've had a 100 gal transferflow in bed tank with a camper shell in various D/A's since 01 without a problem. I use the Transferflow campershell filler kit with it, and have a locking cap on it. Over 200,000 miles of rough Mexico and Central America use without nary a problem. No smell, no spills, no seaps, no leaks, and no failures of the Transferflow pump. The perfect setup for me. I can go about 1800 to 2,000 miles without stopping for fuel.

that's the first person I've come across who has actually done what I am interested in doing. Did you have to redirect any of the venting outside of the camper top such as through the wheel well? the reason I ask is becasue many have said that if they have their rear window open while driving they get some pretty good fumes from the in bed tanks. Part of me would like to be able to let my dog ride in the camper topped bed, but I'm hesitant with the in bed tank, for fear of gassing my friend. I think even if I didn't smell gas, I'd avoid the in bed tank and pet combo anyway, but it's good to hear that you've been able to make it work without any odor, fumes, etc... How difficult was it to install the camper filler kit?

On another note, my two main concerns about the undercarriage tanks are that the TF and the Titan both hang below the rails and the tanks out in Corona,CA that don't hang below the rail will nto ship their Chevy diesel tanks. The other concern is that it sounds like no one can get their LBZ fuel gauges to work with the new enlarged tanks. Anyone know of any way to alleviate these concerns about a larger undercarriage tank instead of or in addition to the bed tank?
Thanks for all<
CAL

2ea. 50 gallon marine tanks in back under camper shell ,no problem with spill or odor. Have pump in line that don't use much,have fuel line going to vent line on truck filler. 3/4 vents on tanks in back of truck.
Three years and works well.