[dubesrus]

2000 V8 Tundra, extended cab with a shell on the bed... 118,900 miles
Only things not stock are a K&N filter and load range E tires 265-75-16 at 50 psi front and 60 psi rear.

I typically get 19 to 20 mpg on interstate or state highways, either unloaded or with a load in the bed. I stay at the posted speed limit and use cruise control anytime possible.
I get 15 in short (4 to 10 miles) trips to and from town, but I drive mostly highway miles.

Towing a small travel trailer I get between 10 and 13 depending on the wind speed and direction.

I have a Shell gas card, so use it to get the 5% off the pump price. I rarely use discount station gas. I use synthetic engine oil and change it and the filter at 10,000 miles.