My man, since you are new I will spare you the talk about using the search function. But just know that this has been asked numerous times in the past, hence the people saying to search or look at the FAQ section.

So, to answer your original question, there are a lot of things you can do to bump your mpg's but you are never going to get great gas mileage so just keep that in mind going in. Personally, I would say the best mod for increasing mpg's is the electric fan. I saw the biggest improvement when I replaced my stock fan with an electric one. After that, there are other mods that will make small improvements like a CAI, exhaust, tuner, etc but you will not see huge jumps with any of these. Also, a good tune up will usually help too if you haven't had one in a while. Hope this info helps, and welcome to the forum

 

another good way to save gas would be walking! jk lol

 

Drive downhill with the wind behind you.

 

Ok guys, newbie OP, first post ever on DF! How about saving the humor for when he gets to know some of you. Let's try to help the guy a little, huh?
I know the "I just bought a 6000 lb. truck with a 345 HP V8, and can't understand why I'm not getting the mileage I got with my VW Rabbit" gets a little old for guys been here a while. But there are numerous things that will sneak an extra 2-3 mpg out of that truck and y'all know it!!!

 

........heh

 

+111111111111

Walking can get you about 50 miles to a gallon of water.

 

OK..OK..Sorry.

Tuner, cold air intake, and exhaust should help you out. It would also help if you have the 4.10 gears. Keep your tires size at about 31-33 inches. Keep the truck down low for less drag. Install an e-fan. All I can think of right now. Hope it helps a little.

 

and if you go on a diet and shed some pounds, it will be about 60 miles to the gallon of water

 

all that and also get some low rolling resistance tires and light weight rims. bed cover should also help in the city mpgs