Poor Highway MPG?

[salvie]

2003 - Tahoe - While I know the 5.3's aren't exactly "economic", I was a bit disappointed in the MPG I got while driving from Pittsburgh, PA to Wilmington, NC. I averaged about 16 to 17 MPG on the trip. All highway and used cruise control 80% of the ride. I probably averaged 70/mph...never went any faster that 80/mph. Normal City driving, I get about 15 MPG. Any one think there might be a problem in regards to the poor highway MPG or is this about normal?

 

[Thumper724]

I have an 04 Z71 Tahoe and that's about what I average.

 

[amtronic1]

15 is it for me too. These trucks are overweight, big, and push a lot of air going down the road. I can pick up a mile per gallon dropping from 70 to 60. But I would get run over out on the Interstate.