LOL.
BTW, it's weird that it is listed in the Cincinnati craig's list, but is in Milford.
Also, it is a 2wd 5-speed - that's what I have (but a 1996) and I can get 21 mpg unloaded / 17 mpg hauling my truck camper and a 6x10 enclosed motorcycle trailer as long as I stay at 2000 rpm or below (3.55 gears = about 65 mph @ 2000)
Ask these questions about the tranny/clutch:
Why was the trans replaced?
Does it have a new clutch?
Is it a single mass or dual mass flywheel?
Dual-mass flywheels are stock. They work well for 30k to 100k miles, and then they die. You get some warning (do a search on thedieselstop.com for "DMFW"), but when they let go, they take the bellhousing out. The ZF 5-speed has an integral bellhousing, so this may be why it has a new trans.
Dual-mass flywheels are almost always changed out for a single mass unit - the trans/clutch will be a lot noisier with a SMFW, but it will be bulletproof. My truck had 2 DMFW that lasted about 60K each before they got swapped out. The first time was under warranty, the second time I installed a SMFW and clutch kit from south bend clutch for $700 parts.
The stock clutch isn't much good for more than 250hp - I did all the mods bones suggested above and ended up slipping in 3rd gear and higher. The DMFW was also getting real noisy, so I replaced it all.
Another thing to keep powerstrokes happy is oil changes religiously at 5k and fuel filters every 10k. The HEUI injectors use engine oil pressurized to ~1800 psi to fire the fuel inside the injector; these pressures plus the shear the oil goes through breaks it down quickly.
At 119k, you're probably close to needing a waterpump, they can be had for about $160 if you know where to look, don't go to a dealer or you may die when you see over $400 for parts.
Bones mentioned glowplugs - you should change them if they're old; about $10 at autozone for the preferred autolite (beru) parts. takes a couple of hours and some patience to swap them out. Use a light touch when taking them out - some can become carbon fouled and be tough to get out. What usually happens is that someone reefs on them, and the tip breaks off and falls into the cylinder. That always winds up in pulling the cylinder head off.
Good luck - I love mine, Bones loved his, regretted selling it and now has another. :sonicjay: