Larger Replacement Fuel Tanks

gcope63 · November 28, 2003

Has anyone installed larger than factory fuel tanks in their '03 or '04 HD's?? Do you have to have the computer reprogrammed so the DIC knows it has a bigger tank??

Thanks

Gary

sbrennan007 · November 29, 2003

Is it even possible to get a larger fuel tank? I am assuming that you are speaking of a larger factory tank. I have a 2500HD with the SB and don't even know if a larger tank would fit...

gunslinger45 · November 29, 2003

Well I've seen lots of different models of auxilliary tanks that fit in the bed of most trucks. That would be a fairly easy addition that can carry a lot of extra fuel, but you give up a couple of feet of bed space. If you're looking for a more "integrated" option that tucks up under the truck then I think your options are quite a bit more limited, and I personally am not aware that I have heard of any specific options. I have an Avy 2500 with a 38 gallon tank from the factory. Given that the HD Av chassis is the same as the 2500 suburbans, maybe there is something out there in the making for a the Silverados, but I doubt it. I have heard talk on the open roads forum (address below) about a company called Jodums that sells auxilliary tanks, but I am not sure of application. Those guys on the open roads forum would know quite a bit though since they love to tow and tow and tow. Check it out and do a search. Good luck.

http://www.woodalls.com/forums/index.cfm

Gunslinger

gcope63 · November 29, 2003

Actually the two I was thinking about was Transfer Flow inc. (www.transferflow.com) and Aero Tanks (www.aerotanks.com) both are replacement tanks and are approx 45 gals for a SB.

Gary

jconro · December 5, 2003

I had the 45 gallon Transfer Flow tank installed on my 2002 2500HD extended cab SB a few months ago. Didn't need to reflash the CPU and it works great. I paid $1100 including installation.

gcope63 · December 5, 2003

I figured the '02 or older would be fine, I was wondering how the DIC in the newer trucks would handle the larger amount of fuel when calculating miles remaining..

Gary

spacebuzzard · December 7, 2003

I have the 45 gal Transfer Flow. The only function that is affected on the DIC is the range. Everything else like MPG, Fuel used and so on works just as before. You have to read the fuel gage a little diff. . I use about 7 gal before it drops off full and when its on empty you have about 7 gal left.. Its no big deal as you adjust right away. The benifits are wonderful. When not towing your range is over 900 miles and you can pick where you want to fuel up. When towing you dont have to pull through the gas islands near as much.

422 SS · December 8, 2003

I have the 45 gal Transfer Flow. The only function that is affected on the DIC is the range. Everything else like MPG, Fuel used and so on works just as before. You have to read the fuel gage a little diff. . I use about 7 gal before it drops off full and when its on empty you have about 7 gal left.. Its no big deal as you adjust right away. The benifits are wonderful. When not towing your range is over 900 miles and you can pick where you want to fuel up. When towing you dont have to pull through the gas islands near as much.

You have a Dmax don't you.I know a 8.1 wont go 900 miles on 45 gallons of gas.GCOPE if you get a 8.1 shortbed expect to get 200-225 miles empty and 130-150 miles per tank towing.

gcope63 · December 8, 2003

ARE422DP

Using those numbers and the size of the tank you are telling me I can only expect to get 7-8 mpg empty driving and 5-6 towing?? I haven't heard of anyone getting that kind of mileage empty or loaded?? I think that is worse than the old 454's!

I would figure approx 300 miles empty and around 220 towing per tank from what I have heard from most people that have them.

Gary

422 SS · December 9, 2003

I'm referring to the stock 26 gallon tank.The best I ever got on a tank of fuel was 250 miles,once.Remember you don't run them completely out of fuel.I averaged 200-225 miles on a tank of fuel normally.The tow mileage is from my experience with pulling a 28ft car hauler that weighs 8500-9000 lbs.Several of my racing buddies have 8.1 trucks and get similar mileage.I put 58,000 miles on a 8.1 truck in 2 years combination city,freeway and maybe 10% towing from 4000-18,000 lb trailers(I Own 4 trailers).The 8.1 averaged 9.7mpg, my current 20,000 mile Duramax truck averages 16.3 mpg.I run 500+ miles on the freeway in the Duramax with a 34 gallon tank.The frontal area of your trailer has a big effect on mileage.Big and boxy will use alot more fuel than a low profile trailer.