20 mpg in city on a 6.2L V8. Love it.

[KCPhil]

I've got 2K miles on my ZR2. So far, my results have run between 15.6 and 18.2 on the highway. I have the 6.2 and would be tickled with 20. BTW - I had a Yukon with the same engine and 'only' an 8 speed transmission and I could get 20 to 22 mpg. So I've been disappointed with this fuel mileage.
I have noticed a significant difference based on the octane fuel I use. The truck was delivered with regular. If I'd known, I'd have told them not to bother. That's the tank I got 15.6 on. With a full tank of 93 octane is when I got 18.2.

 

[XkenX]

I've got 2K miles on my ZR2. So far, my results have run between 15.6 and 18.2 on the highway. I have the 6.2 and would be tickled with 20. BTW - I had a Yukon with the same engine and 'only' an 8 speed transmission and I could get 20 to 22 mpg. So I've been disappointed with this fuel mileage.
I have noticed a significant difference based on the octane fuel I use. The truck was delivered with regular. If I'd known, I'd have told them not to bother. That's the tank I got 15.6 on. With a full tank of 93 octane is when I got 18.2.

 

[XkenX]

Why such the disappointment window sticker is 14 city 17 highway on ZR2? Enjoy the truck and not worry about the hypermile. I thought the 6.2 was premium only. Unless that has changed?

 

[sardarjee]

Sometimes driving conditions are ideal for best city mileage.

 

[ZR2BIZON]

Sometimes driving conditions are ideal for best city mileage.

View attachment 13849

What sorcery are you pulling over there!?

 

[landpilot]

i got 18.1 both ways from Louisville to Memphis and back over Father's Day weekend... that was at about 80mph for most of the way. My city is usually closer to 14 or so...

 

[sardarjee]

i got 18.1 both ways from Louisville to Memphis and back over Father's Day weekend... that was at about 80mph for most of the way. My city is usually closer to 14 or so...

For about 700 miles over weekend at about 70 mph I got less than that

 

[KCPhil]

Why such the disappointment window sticker is 14 city 17 highway on ZR2? Enjoy the truck and not worry about the hypermile. I thought the 6.2 was premium only. Unless that has changed?

The manual says...
"Premium unleaded gasoline meeting ASTM
specification D4814 with a posted octane
rating (R+M)/2 of 91 or greater is
recommended. If unavailable, unleaded
gasoline with a posted octane rating of
87 may be used, but will result in reduced
performance and driveability."
The dealer didn't bother to go into all that detail. He just said, "You can use regular if you want to." Having had the 6.2 in my Yukon, I knew better. And, actually, the Yukon recommended 93 octane tier 1 gasoline.

 

[XkenX]

The manual says...
"Premium unleaded gasoline meeting ASTM
specification D4814 with a posted octane
rating (R+M)/2 of 91 or greater is
recommended. If unavailable, unleaded
gasoline with a posted octane rating of
87 may be used, but will result in reduced
performance and driveability."
The dealer didn't bother to go into all that detail. He just said, "You can use regular if you want to." Having had the 6.2 in my Yukon, I knew better. And, actually, the Yukon recommended 93 octane tier 1 gasoline.

You could have added octane booster but not to much, otherwise its just wastes it because motor just wastes it because of tune. I used to make about 30 trips a year 800 to thousand miles about 3 years straight. Just the truck stops, locations and quality of fuel varied fuel millage by at least 2.5 miles per gallon. Add wind and weather some trips 21.5 avg at 80 mph on a 6.2 others 14 or 16. Light trailering, loaded truck 50 percent time ended up averaging 16.9 mpg over 47000 mile recorded in that span. My 5.3
Suburban never did over 15 on its best day.

 

[AXE]

Did this yesterday in my wife's Tahoe 6.2L Downhill trending lots of tight curves and small grade changes 25-65 mph. Should have been on my Ducati, it gets 45 mpg even in the twisties under high rpms or with the front wheel in the air.

 

[DNZR2]

For some reason mine gets better mileage in the city commuting to work than it does on the highway. 17 city 14 highway

 

[sardarjee]

For some reason mine gets better mileage in the city commuting to work than it does on the highway. 17 city 14 highway

Yes. Seems like DFM kicks in at slow speed.

 

[XkenX]

For some reason mine gets better mileage in the city commuting to work than it does on the highway. 17 city 14 highway

A lot of times in the city you can get a better draft if traffic flowing steadily.

 

[hhpd]

I get Great mileage downhill--