Real World Gas Mileage for your 5.3's

[mikew2069]

My Tahoe now has about 1000 miles. On my first tank, w/ the stock 17" wheels, I got 17.5 mpg. That was a mix between highway and city driving so I was very impressed. Then I put on the 22" wheels and milage tanked. The 2nd tank I got 14 mpg but it was mostly city driving. I am now on my 3rd tank w/ mostly highway driving and it looks like I'll get about 15.5 mpg.

I am actually suprised that the wheels made such a difference... I guess I'm doomed. I'm thinking about adding a catback and cai system w/ hopes of gaining a mpg or two...

 

[73shark]

My Tahoe now has about 1000 miles. On my first tank, w/ the stock 17" wheels, I got 17.5 mpg. That was a mix between highway and city driving so I was very impressed. Then I put on the 22" wheels and milage tanked. The 2nd tank I got 14 mpg but it was mostly city driving. I am now on my 3rd tank w/ mostly highway driving and it looks like I'll get about 15.5 mpg.

I am actually suprised that the wheels made such a difference... I guess I'm doomed. I'm thinking about adding a catback and cai system w/ hopes of gaining a mpg or two...

Did you get the computer reset for the 22s? Was your mileage from the DIC or actual calculations?

 

[mikew2069]

Did you get the computer reset for the 22s? Was your mileage from the DIC or actual calculations?

The mileage is the same from the DIC and the calculator. I asked the dealer about resetting the computer for the 22s and they said that the tire shop was supposed to do it?? .... I have not taken it to a caddy dealer though...

 

[dredmond24]

There is no need to have your computer re-flashed, if the rolling diameter
(31.63") of your tires hasn't changed. I have Falken 305\40\22 on my truck.

 

[mikew2069]

There is no need to have your computer re-flashed, if the rolling diameter
(31.63") of your tires hasn't changed. I have Falken 305\40\22 on my truck.

Thats what I was thinking, but it seems like everyone recommends getting it flashed...

 

[Seats9]

1500 miles in

After having the Tahoe now for about 1500 miles the average mileage is 19mpg. That is about 1/3 city driving and 2/3 highway, 70-80mph. I have tried to kick it back lately after what I have read here, and the AFM is set up to maximize mileage at 65mph. I will just have to start leaving a little earlier I guess!!
David

We bought it used and it now has 21,000 miles total.

 

[izmir2002]

i have 45000 mile on my z and im getting 16mpg

 

[dcovell]

What about the 6.2 Denali's out there? What are they getting? I have a theory that the larger engine with the 6 speed transmission will be able to keep much lower RPMs on the highway and will get peak gas mileage on the highway. Can anyone back that up?

 

[73shark]

What about the 6.2 Denali's out there? What are they getting? I have a theory that the larger engine with the 6 speed transmission will be able to keep much lower RPMs on the highway and will get peak gas mileage on the highway. Can anyone back that up?

Lower rpms don't necessarily equate to better mpg. For example, when I'm below 60 mph, I can engage tow mode which drops it out of OD and the rpms go up, but it also kicks into V4 mode if on level or slight incline. MPG goes way up.

 

[p26963]

17.5 mpg on a 840 mile round trip. 90% freeway mostly level, if not slight inclines. Mostly cruise control going 75-80 mph. 3.42 gear ratio 2WD.

 

[07TahoeLTZ]

Were you getting any 4 cylinder mode....

17.5 mpg on a 840 mile round trip. 90% freeway mostly level, if not slight inclines. Mostly cruise control going 75-80 mph. 3.42 gear ratio 2WD.

During the trip?? I would like to see if anyone is getting into 4 cylinder mode with 3.42 at around 70mph on flat roads...thanks!

 

[izmir2002]

As far as i know only the powertrain have 100000 mile warranty.bumper the bumper is 36000 mile !!!!

 

[p26963]

No 4 cylinder mode here... only on the downslopes. It mainly stayed in 8 cylinder mode.

During the trip?? I would like to see if anyone is getting into 4 cylinder mode with 3.42 at around 70mph on flat roads...thanks!

 

[mikew2069]

No 4 cylinder mode here... only on the downslopes. It mainly stayed in 8 cylinder mode.

Same here...

 

[txshriner]

6.2 tahoe LTZ

i just got a tahoe LTZ with the 6.2, 6 speed auto trans and 3.42 rear. it turned 499 miles last night. ive only used 1 tank of gas. it went 390 miles on 26 gallons which was a little over 16mpg.