20mpg average possible?

[HERD546]

My 09 Tahoe Z56 PPV is showing 14.5 MPG average on the system. I am planning to add a Detroit Tru Trac posi unit to my truck. I have been thinking about a gear change from the 3:73 to a lower gear. Just wondering what I can expect in mileage using a 3:42, 3:23 or 3:08. I am willing to give up a little get up and go for better fuel mileage.

With my 95 Caprice wagon with the LT-1 5.7 and a 2:56 I was getting 23-24MPG going 75.

 

[MudnRox]

I use the cruise control when on the hwy and usually have it set at 75. I have the tow package so my gears are 3.42s. I constantly see 19.5 mpg on road trips. My hand calculations are always within .2 miles of what the DIC shows. Around town in mixed hwy/city driving I usually see anywhere from 14.5 to 16.0 mpg. I'm a light footed driver but certainly no grandma by any means.

 

[Big Buttons]

14 avg and I drive like an *******.

 

[jdpber]

Good tuning. Factory size wheels and tires. Performance intake, clean TB, clean injectors. Do rolling starts. And easy on the peddle. Flat freeway with cruise set 70-75. Yes 20+ is very achievable.

If I can stay in OD on a flat freeway I can hand calculate 21 is my best. Constantly getting 19 on freeway. Town I am 16-17 consultant with hills. Now I am dialed in and about every 4 weeks or so my busy and I fine tune my tune. So that helps. Not everyone has this convenience. But yes it is possible.

If I hammer down I am 12-13 town. But that is rare.

 

[al2fast]

I'm between 19 & 20.5 on freeway with cruise set at 73. 09 denali with 3.42 gears. Haven't checked since the tune but have been a little lead footed since then way better than my 08 Sierra Denali that would top out at 17 on the best days. Pleasantly surprised with the mpg gain going to yukon denali.

I do have all season Bridgestone Alenza tires now and my sierra had the cooper zeon ltz tires. I'm sure those hurt the mileage.

 

[ccapehartusarmyINF.(ret)]

anyone who just posted on here claiming there getting 20mpg your either really bad at math or drives 25mph or just plain full of it most tahoes get 15 to 16 20mpg is almost a 25percent increase and if black bear tune claims a 25percent increase in fuel economy there lying to you

---------- Post added at 02:27 AM ---------- Previous post was at 02:26 AM ----------

also since GM grossly exagerates the fuel economy of there vehicles

---------- Post added at 02:36 AM ---------- Previous post was at 02:27 AM ----------

so i call BS

 

[jdpber]

I do not have black bear. And you have to milk the hell out of the car to get it. And only happens on freeways that is flat and needs to be long distances.

 

[TheAutumnWind]

I am averaging 13mpg ATM. Mostly city a few tanks of gas ago it was more like 11mpg.

 

[Nashoba]

Yep, according to the computer in the vehicle. 20.5 average MPG in our 2008 Tahoe Hybrid through 102,145. I just went to the garage and checked it. Of course my wife drives it most of the time, though. She does not have a lead foot but she does drive near 70 on the two lanes and near 75 on the four lane roads. Don't have a clue as to the accuracy of the computer but I think it is close.

---------- Post added at 09:20 PM ---------- Previous post was at 09:15 PM ----------

Thinking about a 500 mile tank, I used to work about 488 miles from the house and sometimes my wife would come to see me on weekends if I did not go back to the house. She always was able to drive the 488 and then to our favorite restaurant, another 20 miles round trip before we filled it up. I could run that far in my '05 Avalanche but it had a larger tank but I drove faster so I just barely made the trip on a tank.

 

[Nealgobert]

I was able to get just over 20mpg hand calculated once on a trip when I was stock. And I stress once lol.

 

[Deephaven]

My truck may or may not be able to, I'll never know since there is no way in hell this driver could.

 

[redeknightjr]

I have a 2000 LT new body style.....it has just over 200,000 miles ...K&N cold air intake and super 40 muffler are the only mods Ive done for performance. I do use super unleaded. I have consistently been getting about 370-395 miles to a tank 80% highway. I think that is pretty good

 

[Nashoba]

Hey, redeknightjr. Howis the internal resonance with the super 40s? I have a nice exhaust on my 2011 Silverado but the '08 Tahoe Hybrid is still stock exhaust. It is still pretty quiet. I wonder if it will be rather odd to run up to 20 mph and then have the engine start with a blast? Might be kinda cool.

 

[redeknightjr]

Nashoba.....with the side exit it is not bad at all....conversation is not hindered at all