I currently have a company owned impala that is at 106k miles. We usually trade out at 100k, or 3 years, and with the timing of our fiscal year, I had to place an order. I placed it today (9/7/05) through the local dealer's GM fleet and CAPS program my company has. I decided on the Crew Cab 2500HD with the duramax/allison, and wanted the LBZ, but with all of the outside factors, the time was now to place the order. I would like to purchase this vehicle from the company at the end of the 3 year period, at which time I'd like to do some upgrades. I ordered the 1LT 2WD, as I couldn't provide enough justification for the 4wd.

Couple things:
Am I destined to end up with the "tweener" LLY?
What kind of mileage can I expect?
I will be pumping fuel from our company diesel tanks (I work for a trucking company), what do I need to do for fuel filtration?
How does the 2wd fair when upgraded (when I can do this in 3 yrs)?

Thanks