Poor gas mileage on 94 GMC Sierra 4x4

[sevenup]

Hello, What is the average MPG on a 94 GMC Sierra 4x4 ? 5.7L
I'm gettin approx 15 MPG.
Does anyone have any tips or tricks to improve this ?
Al.

 

[Sam Chicklets]

have the catilyst converter checked, it may be plugged. Also when was the last time it was tuned up?

 

[sevenup]

No cats, also has custom exhaust.
Tuned up 2 months ago.
Did some checking online, from what I read 15-16 mpg seems to be the norm.
Just seems real poor to me. Its a nice ride all all, just a guzzler.

 

[RacingFan]

I'll trade you: my '97 4x4 5.7L gets <14 combined highway and city driving...