Hello C8 lovers!
Have not used mine at all this year yet, however I did start her up and dive her home and back, about 4 miles the other day.
Now, having run mine for 3 years I am getting a pretty steady 8 -9 MPG this having talked to other owners is about as good as it gets.
I have improved mine slightly by dis conecting the front drive shaft.
Rick, you are right, you get permant (unless you remove the front shaft) 4 wheel in 1st and Reverse, the leaver near the battery box is to engauge 4WD in all the other gears, I have tried mine and it did work fine.
The red light on the ign Switch is your charging light, should glow until engine runs correctly showing that correct charge is being generated.
And finally yes correct oil level in air cleaner is a must also check reguarly your fuel filter, they are only small and block or restrict fuel flow.
Regards
Jules