5.7liter vortec fuel economy

[natemc]

I'm trying to get a baseline before I do any modifications to the wifes DD. We have been losing fuel economy since we put the new short block in it last year. Also, for those that are interested, this thread should be a good tool. Please keep it to the 5.7l powered rigs. We could start another for other engines

Copy, Paste, and Post the following please!

Year:
Model Vehicle:
Transmission:
4wd/2wd:
Gear Ratio:
Tire size:
Current MPG - HWY/City:
Usefull information or mods:

 

[natemc]

Year: 1999
Model Vehicle: Yukon
Transmission: 4l80e i think, will verify
4wd/2wd: 4wd
Gear Ratio: 3.73 i think, will verify
Tire size: 245-75-16
Current MPG - HWY/City: 14/12
Usefull information or mods: All stock

 

[George_Pimpdaddy]

Your Yukon will have the 4l60E like my Tahoe has.

Year:1999
Model Vehicle: 4 Door Tahoe
Transmission: 4L60E
4wd/2wd: 4x4
Gear Ratio: 3.73
Tire size: 265-75-16
Current MPG - HWY/City: City-12mpg
Usefull information or mods: 14 bolt SF rear, rebuilt 350 with 15,000km, K&N filter, Quaker State 5W-30 synthetic, synthetic oil in axles too.

 

[Bowtie85]

Year:1997
Model Vehicle:1500 SLE
Transmission: 4l60e
4wd/2wd:4x
Gear Ratio:3.73
Tire size:33x12.50x15s
Current MPG - HWY/City:16 ish hwy, 12 ish city.
Usefull information or mods: Headers,dual exhaust, gutted cats,shift kit, K&N intake. 14 bolt s.f rear.

I used to have stock wheels/ alum mags with 265/75/ 16s and got around 18 mpg hwy and 14 city. Havent really used it much since I put the 33's on.