My m1008 also gets around 17 mpg. The m1008's are geared low: 4:56. Don't expect to win any speed trials as 55 mph is about all you'll get--60 if you're late for school, work, etc. M1008's are loud and ride rough: that's what I like about them! IMHO stay away from any 12 volt conversions--the thing is going to drive you crazy enough with its incessant maintenance. Having said that: my m1008 is extremely reliable, with the most major repair a broken flywheel. The transmission separated from the engine because of vibration and broke some of the attaching bolts. Even with the center broken out of the flywheel, the truck still drove 15 miles to the shop.
!DON'T EVER USE ETHER!
I've used ether a couple of times , but only after unplugging the glow plugs! The last time I used it, I swore I'd never do it again because it creates an engine over-speed condition. Find a good alternator repair shop-you'll thank me later. Having said all of that, I would get in that truck and drive it anywhere. It's my daily driver and I trust it. The engines aren't strong, but they are reliable-and with a properly functioning glow plug system will start in almost any cold weather situation. Perform regular maintenance and the truck should last you a long time. Is that enough or do you need more?