This last weekend, I did it again! Went to another location and did around 40 miles on gravel. I get anywhere between ~30-42MPG because I have to crawl in 2nd gear most of the time at ~13MPH. If I could go faster, the washboard roads were too brutal (ever been in a paint shaker?) and any slower was 1st gear and MPG down to nothing. Overall trip was 150.9 miles and 65MPG. (tank was sitting at around 88MPG before this, now around 75MPG).
Here's a pic from that adventure.