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alvero
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Discussion Starter #1
My 2002 lb7 has the edge juice with attitude installed and had 265/70/16's on the stock alloy wheels. Summer time on stock power level I would get about 13.5 mpg; level 1 gave about 14-14.5; level 4 gave about 15.5.

Well I had discoverer stt 265/70/17's put on and now level 4 is giving me an average 13.4 and level 1 is giving 12.7!!!

I don't understand why, they aren't very much taller and they should be the same width, right?

Anyone else see a mileage decrease with discoverer stt? Would getting some sort of street tires help efficiency?
 

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I went from a 285/75/16 on factory wheels to 285/50/18 on 18X9 wheels and had seen a difference. 285/50/18 is actually close to a 265/75/16 but there is more rubber on the ground and the wheels and tires weigh more.
 

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Wheels is a big thing and the tires themselves might have made a difference i went from 275/70/18 to 295/65/18 and my gas milage went from 15.5 to 14.3
 

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Edge's mileage setting is junk.....I always ran mine on 3 or 4 to get decent mileage out of it. I typically just kept mine on 5 though...Lol
 

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Is that the only mod you have that's isn't the greatest mileage for an lb7
 

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alvero
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Discussion Starter #6
I also have banks dual monster exhaust with muffler delete. Another thing I was wondering is on the cts screen the corrected speed is lower than the speedometer, like when corrected speed is 65 the speedo says 72.
 

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I have a 2010 Duramax. I just did a run from Chicago, IL to London ON and averaged 19.9 MPG. One stretch of road was 55MPH and while traveling on that stretch the computer showed 22.3MPG. My truck is stock other than I added two Fuel Genies, one to the intercooler intake and one to the air intake. I wasn't hauling anything at the time, just stock truck on stock tires.
 

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wow I got better mileage than you in my 1500 with 35's, in my 2004 lb7 on edge level 3 with banks intake and 4 inch straight pipe I get 17 mpg city driving no problem at all and about 25-27 on highway. running stock tires right now, putting on 35" open countries soon so will let you know
 

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alvero
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231 Posts
Discussion Starter #9
My injectors are getting pretty worn I think. My 2005 lly is very quiet compared to the lb7. In drive injector number 4 balances at about 4.3, number 2 at about 2.8 and the rest are within +-2. neutral they're all within 3. Could old/worn injectors be a cause or contribution? These have about 117,000 miles.
 

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#4 would be the worst but not quite out of spec yet
 

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thats low milage for an LB7 anyway. My '02 with 35'' tires gets 17.5 all the time (hand calc.) Might be something else going on IMO
 

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well my mileage is always around the 15 mark so if something else is wrong let me know
 
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