lite v heavy loads
 

how much does a lite vs heavy load affect your fuel milage? not sure if it was just a bad trip but i'm seeing a easy 1.2mpg difference. 78k gross vs. 47k gross

It does indeed have an effect. But then so do many others. Wind speeds/wind direction and a host of other things affect it too.

Mine can be 2-3 mpg different. If I run a flat area it can be lower, 1 mpg difference. Headwind vs tailwind can really make a difference too. Weight though, oh yeah, that can cause a difference.

Don't forget this time of year you're using "winter" blend fuel if you're in the North, that will cut your MPG some also. I lose about 1 mpg every winter just because of the fuel, I see an even bigger drop with my pick up truck it's got an old mechanical injected engine and doesn't even try to compensate for crap fuel.

that is something i was definitely thinking about. it might be the blend the truck was running all screwy for a bit.
i was in heavy winds. however also really pushing my little 435 as well.