Need help with getting a little more performance and mpg out of my 5.3

Hey there everybody I'm new to the site. I have a 2002 1500 Z71 with the 5.3. Lately my mpg has been getting pretty bad and I just got done doing a tune up to it. Also like most I'm looking to get a few more horsepower. If anyone knows some way to combine the both but stay within a realistic budget I would really appreciate the help. Thank You  

the fuel pressure regulators on these can go bad.. killing your power and mileage..



the fuel filters can also clog..  reducing fuel to the motor..
the fuel pumps also have been know to wear out.. usually do to running really low on fuel... or do to a clogged fuel filter.

is your check engine light on??????   when some trouble codes set.. the ECM backs off on the power and pushes the fuel mixture rich to not damage the motor..

driving like you stole it is always hard on the gas mileage..

the engine has to be in normal operating condition for the ecm to really fine tune it for best MPG.....  

The check engine light isn't on and driving like I stole it was earlier when I got the truck but now I drive like a grandma trying to get better fuel economy seeing as my income has gone severely down. I hate to say it but I did look over the fuel filter and the pump but I know the fuel filter doesn't cost much but how much do the fuel pumps run. Also are there any reasonably priced bolt ons that could possibly help? The help is greatly appreciated.  

try a hand held tuner,and get a after market air intake kit.  

garygnu:
try a hand held tuner,and get a after market air intake kit.

wrong, it doesn't sound like this guy likes to flush his money down the toilet  
2003 Chevy Silverado

you have a 4.8/5.3/6.0? you need: cold air intake, exhaust system and a tune, see my posts for more details!