5.2Liter gas mileage

I have a 99 5.2 liter dodge ram, its 4x4, reg. cab, swb. with an automatic trans. I have been getting around 12mpg., now the trans. is out and the second 02 sensor is bad, im fixing to take it to the mechanic, does anyone have any ideas on how i can get better fuel mileage or any slights mods. the mechanic might can do or i can do, i would like to get by as cheap as possible since i am in college and all. What kind of mileage should i be getting? Thanks any help would be appreciated

From what I have been seeing getting around 13 or 14 is what you should be getting around the city. I believe it is up to about 17 or 18 on the highway at 65 mph. I have a similar truck as you but a little later year wise. Mine is a 5.2L v8 2001 Shortbed Manual. I just bought it last week but have figured up my gas mileage is abotu 13.5 mpg right now. I figure once I get used to manual trans again I might improve a little but I am not expecting much. As far as slight mods I really have no idea but I figured I would elt you know what I do know.

there is another thread that would be wise to read the thread is "Help! Need Better Gas milage". This will tell you that there is a few things you can do but nothing that will give you remarkable gas milage!

I have a 98 QC swb 4x4 with 5.2 auto, I'm getting an average of 15 mainly city driving. all I have is K&N and cheap exhaust.

Synthetic oil, though it seems expensive to buy, may get you 1mpg (or more) which would be cheaper overall.