2007+ GMT-900 Gas mileage?

[rs-mn]

What gas mileage are you getting with your new style 2007 GMT-900 truck?

 

Please mention if you have 2 or 4 wheel drive, auto or manual tranny and the gearing/tire size.

 

(I'd be interested in what a 2007 1500 Crew Cab LT1 4x4 with a 5.3l or 4.8l & 3.73 gears is getting.)

 

Also, if you have tried E85, please report that mileage too.

[pm26]

I happen to have an '06 Silverado Z71 crew cab LT1 with a 3.73 gear ratio, so I throw in the gas mileage for comparison: 15 city, 17 highway.

4x4, 5.3 liter, 4L60 auto, OEM P265/70R17 tires, alloy wheels, autotrac transfer case, fender flares, moulded splash guards, fog lights, open bed, tailgate up, use 89 octane gas.

[Big Tool]

07 sierra 6.0, 4.10's 16.8 on the interstate, about 13 around town. I just got over 500 miles so it should improve some.

[HawkeyeOC]

07 Sierra Crew Cab 4wd 5.3L with 3.73 gears. I got nearly 20 mpg today in the 50-60mph range. I average in the low to mid 15's with a mix of hwy/city driving which is just a little under what my identical '06 5.3L with 3.42 gears was averaging. Adding the tonneau cover on that truck bumped the average mileage up into the mid 16's.

 

It's rather interesting to note that with DOD and 3.73 gears on the GMT-900 the gas mileage for me is nearly the same as my GMT-800 '06 with 3.42 highway gears!

[cerbomark]

07, 4.8, 3.42, 20 in wheels, 4x4, 1500 miles, 18-19 highway @ 65-75 mph. 14.5 mixed driving all on winter blend regular fuel. I got to admit I m a little disapointed, thought it would be better.