So to finally put any confusion to rest about the specs on the senders/sensor for the fuel level on the factory returnless vs return systems, here it is from the GM service manual:



04+ on the left, 99-03 on the right

04+
Empty - 250ohms
Full - 40ohms

99-03
Empty - 40ohms
Full - 250ohms

 

So........... not gonna swap over i take it, lol

 

Not directly, but you can fix it in HPTuners by copying the Primary Volume and Gauge Primary Volume tables over. I just did this on a truck I did the 04+ tank swap on, worked fine.

 

If one was doing a fuel cell on a +04 truck and elected not to use a factory fuel bucket/fuel level sender. Could a 240-33 ohms sender be calibrated in HP tuners to work with a factory gauge?

If not, the other option could be to use the 0-90 ohms sender that comes standard with the fuel cell Im looking at. Along with Speedway's Fuel Level Gauge Sending Unit Interface Module. The only issue there is the Speedway part maxes out at 240 ohms and the empty reading may be effected.

Which route would you suggest?