Re-Program Fuel Quantity?

[Turist]

You may remember my truck, 2006 Silverado with LBZ motor, the one that was converted from left to right hand drive.
The truck is going well, no issues at all, except;
We have fitted a larger capacity fuel tank, 200 litres.
Is it possible to re-program the fuel system to tell it that it has a larger capacity?
Problem at the moment is that the gauge stays on full until the fuel level drops by about one third.
The only way that we can estimate the true volume in the tank is by noting the "Fuel Used" on the driver controls.

Any help appreciated.

Regards
Bob

[DmaxMaverick]

I don't think you have a "reprogram" option. The computer only knows what it is told. If you are using the OEM sender, it can only send an indication relative to its range. Sounds like your tank is taller (deeper) than OEM. If that's the case, you could modify or fabricate a new float to show the full range of the fuel level. I've done this for other applications with positive results. In most cases, all it involves is to calculate the % difference in the range before/after, and increase the length of the float lever accordingly. Then, adjust the vertical postition of the float to travel the actual vertical fuel range with the sender.

I doubt you'll get it to be accurate, but surely no less accurate than OEM.

[Turist]

Thanks for that Dmax, we will drop the tank and give it a go.
I was hoping that we could, via the computer, tell the system the fuel quantity as well.
This would then enable the "Range" reading to operate with some accuracy.
Thought that it may be possible as different Chev models have different size fuel tanks.
Maybe the programming only allows for the "standard" sizes as fitted by the factory.

I have not seen any mention of replacement underbed tanks on the forums, is it not a popular conversion in the US?
With the distances that we sometimes need to travel between major centres when travelling outback the standard tank is far too small.
We akso have a bed tank of 150Lt with a transfer system to the underbed tank.

Regards
Bob

[DmaxMaverick]

You may be able to program it for the quantity to keep the DIC near accurate. You will still need to get the sender close to an accurate range for it to work, though, because the computer uses the sender input for fuel level and driving range indications.

Several folks here have installed aftermarket fuel tanks. A popular brand is Transferflow. They make larger tanks to replace the OEM. 45 gals for short beds, and 54 gals for longbeds. There are other volumes and manufacturers, as well. In-bed aux. tanks are also very popular.

I have considered increasing my fuel capacity many times, but really can't justify it. Even towing my 14K 5'er, I can go 300 miles on a tank, and usually fill up around 200. I travel with family, so I'm stopping at least that often. Obviously, I don't have your concern with the travels in the outback. The closest I get to the "Outback" is a restaurant chain by that name.