Running with JCT, Part Deux

Freightliner explained to me that each side of the tanks draws fuel. I think my problem is they pick ups aren't drawing equally.
I'm doing this to test that theory......
When fueling I'm only filling up one side before I start on the other side. I've done this twice, once each starting on driver side, then starting on passenger side. Both times I have put approx 20 gallons more on driver side. Before I get my 1st PM, I want to have a dozen or so "tests" and present that to Freightliner and they can take it from there.

 

It's my belief that the tanks start equalizing right away. I don't trust leaving a nozzle going unattended. I fill the right tank first and then the left tank. I've seen the gallons being approx 30 or so and think "heck yeah I'm getting a shower outta this fill up". Usually only to fall short of the magic 50 mark. My company's tanks are only 70 gals per side.
Also unless the sending units are now "sonar based" Freightliner should be able to pull it out and move the float while watching the gauge on the dash as well as what the ecm sees. That's how I used to do it in a previous life as a mechanic.

 

Freightliner explained that they haven't had tank cross overs and equalization since 2012. They do equalize but it's a SLOW process when the refine is off as the fuel had to run up thru both pick up tubes and equalize that way.

 

Put 155 gallons in. Full 1/4 tank off.

 

Yep, this is what was explained to me on my 14 when I had my pickup plugged in one tank. I would have one tank full one tank empty because of that, and with the truck off overnight, it would slowly equalize thorugh the returns and gravity.

Also, you can adjust the fuel economy on the scanguage to kind of account for usage. Mine is set to where when I fuel up from empty, then do the fillup on the scangauge, I'm usually within 1 gallon + or -. And that includes APU. So my scangauge slightly lowballs MPG to account for the APU. When I'm looking at Tank MPG, its taking APU usage off it already. The only way I could get even more exact would be pen and paper.

 

Is...is your needle buried in E with no light on?

 

I agree I've done that on my truck too and noticed that the right tank still pumps for 18 more gallons after the left tank shuts off after filling

 

I didn't even notice that. It is however, the only pic like that. All the others have the light on.

 

Darn, thought I stumbled on a clue, that the gauge is reading correctly because the light is not on so it knows you actually have 40-50 gallons, but the physical needle is just borked. And may need to be "calibrated" some how....just a fluke shot I guess.

 

I really believe it's as simple as what I said above. The tanks are feeding fuel at 2 different rates.