I won mine for $5,500 after auction fees and shipping. I have just over $9,200 in mine. I would have saved a lot of money if I had known the condition of my truck because I could have drove it home, even at 6 mpg. The only things wrong with mine was the passenger door won't open, there were some bolts missing on the heater/blower unit and one nut missing on the mirror on the drivers door. (Nothing that would have stopped me from driving it)
My truck had 9,982 miles on it when I got it. When I had it commercially inspected, they went all over my truck. They jacked it up and literally checked everything. The inspecting mechanic told me "other then it's age the truck is just like new, with no noticeable wear." Everything works, heater, hydrolic unit, lights, horn, CTIS, and dosn't register any air loss during an air loss test of the air brakes.
I do need some new fan belts, they just started squeaking occasionally.
As for changing out the transmission fluids. The 2 filters can be bought on ebay for around $50. After checking Allisons specs on fluid.
http://www.utxchange.com/pdfs/MechanicsTips/MT2923EN.pdf (a lot of useful info in this pdf) I found some dextron 3 fluid that meets or exceeds Allison specs (listed on the labeling) for $80 per 5 gallon bucket. If you let your truck warm up though they shift just fine.
My air filter looked brand new. All fluids appear recent also.
The vehicle condition report on my truck said it needed to be jumped to start and would not start again without a jump start. However this was not the case. The truck fired right up for Bikeman when he removed it from the lot to take it to a local loading ramp for me.
I hope this info help,
William