8 mpg by driving 55

Why does it say to not use additives?

 

23500 empty sounds heavy even with apu

 

I checked it quite a bit topping off and resetting each time. It always was off. The higher mpg the bigger the difference

 

Max Torque range

 

I'd imagine they are referring to this:
Fuel Treatment

 

Probably because of possible damage to emissions components. Lucas, for example, claims to comply "with the federal low sulfur content requirements for use in diesel motor vehicles and non-road, locomotive and marine diesel equipment engines." That's LSD, which is only acceptable for use in vehicles through 2006 that do not have DPF. If you've got an '07 or newer DPF equipped truck, you need to meet the ULTRA low sulfur diesel (ULSD) requirements. It's far easier for the OEM's to say "no additives" than to have PO'd customers that didn't read the label close enough and put the wrong stuff in their tank.

 

This is the Lucas your talking about? https://www.amazon.com/Lucas-LUC10013-10013-Fuel-Treatment/dp/B000FW7V50

 

I rarely use Lucas fuel additive.I hear it’s real good for injector lubrication. I should use it as my mpgs always increase enough to pay for it.Anything that runs on #2 Diesel definitely won’t be hurt by any conditioner or some Kerosine for that matter.Cheaper too.

 

Correct that's the reason. Should I use it?

 

Ive gotten that much in certain areas of the USA at 63 in a Century back in 2001.

I do not drive 55 unless it's upgrade.