Buying a truck, need advice!

[1badtitan90]

I had a Nissan Titan as well.. Didn't pull worth a **** due to light weight springs in the rear. Would sag terribly.. had the power but would really have issues with shifting up and down a lot... average mileage was no matter how I drove it was always 12mpg.. with a trailer, without.. pedal on the floor or idling..