first tank and with my foot in it a good bit 14 mpg. 6.0 4x4 ec/sb 3.73's on 20's. im in the mountains so the DOD doesnt do much for me, stays in v8 mode like 95% of the time. only goes to v4 mode with foot off the throttle or going down hill or really babying it on level ground. about 500 miles on it now, it may get a little better as it breaks in all the way.

 

Once It Breaks In More It Will Go Into V4 More Often.

 

I think its a waist of technology and 95% a marketing ploy. I know very few people with those 07' Tahoes that are supposed to get 22mpg that even get 19mpg. I can get 24mpg with mine with the cruise between 70-72 with the mods listed.

lean cruise mode needs to make its way to the states!!!!

 

Running lean makes NOx emissions go sky high though. It's a trade off, less fuel, more polutants

 

I think the larger trucks it won't work as well as smaller ones (RCSB). My 5.3 powered RCSB is meeting the rated specs with only 300miles on the clock, and that is with starts to show it off to friends, almost all city driving and several 10 minute warmups (funny thing, at work, do the remote start to let it warm up and twice now I have gotten to the truck just as it shuts off!!! ).

My Sis has 07 tahoe and can get rated mileage but she usually drives 10mph over the limit.

If you have the DIC, the instant economy thing really is amazing to watch, you can see how your driving affects mileage, everyone should have that display. Its in V4 mode probably 40% of the time, and would be more if it wasn't for the traffic lights.

Give it some break in miles, should get better.

 

my wifes tahoe does not get the sticker gas mileage at atll...

last time we went out of down it gave us 17.xmpg it would NOT go into v4mode at all while it was on cruise control.... I am really disapointed, the only time it went on v4 mode was on a little down hill or something... I cant believe I get better gas mileage with my cammed/stall/gear 6.0

 

there has got to be something in the tune that you can adjust to get the v4 mode to come on more..

 

I think the V4 mode is going to be more usefull to the trucks with the 4.10 gear where the engine is under less load % at cruise.

 

Weird. Wonder if its a weight/gearing or road thing? I don't know how often it goes into v4 mode but she did check on next fill up and mileage was about rated. Maybe she had a tailwind???

 

You say your in the mountains, what elevation are you at? Our tahoe was getting about 23mpg in Colorado but by the time we got back home to sealevel we were lucky to 18.

After a few thousand miles take it easy on a whole tank then check it. I'd like to see the difference.