Gas mpg?

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SabrToothSqrl

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LS

the LS has the 4.8L vs the 5.3L in the LT+ or massive 6.2L

Sometimes getting the smaller engine backfires on MPG.

and by sometimes I mean always.

You can always give a bigger engine less throttle off the line, but you can never give a smaller engine more throttle.

the EPA may say the 4.8L gets more MPG, but they don't drive in the real world... the 5.3 seems to be the best HP / MPG combo.

the 6.2L however is wicked fast fun :)
 

rogersinsel

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the LS has the 4.8L vs the 5.3L in the LT+ or massive 6.2L

Sometimes getting the smaller engine backfires on MPG.

and by sometimes I mean always.

You can always give a bigger engine less throttle off the line, but you can never give a smaller engine more throttle.

the EPA may say the 4.8L gets more MPG, but they don't drive in the real world... the 5.3 seems to be the best HP / MPG combo.

the 6.2L however is wicked fast fun :)

Exactly why I was asking. I think you can opt out in the LS trim, but I am not sure. If he has the 4.8 he may also have the old 4 sp transmission. that whole combo doesn't bode well.
 

bigblue

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I have a 2007 and I get about 15-16 and that is not stop and go traffic. I don't have a light foot either, but even going easy I still have not seen improvement. I was thinking about getting a BB tune, but was still undecided.


ok...stock mine got 21mpg with the 2007 4.8l v8. I put 26inch wheels on it and had it tuned by black bear and now i get 17mpg with 26s...your numbers sound wrong to me to be stock, and by no means do i drive anywhere close to a grandpa style...
 

phileaglesfan

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the LS has the 4.8L vs the 5.3L in the LT+ or massive 6.2L

Sometimes getting the smaller engine backfires on MPG.

and by sometimes I mean always.

You can always give a bigger engine less throttle off the line, but you can never give a smaller engine more throttle.

the EPA may say the 4.8L gets more MPG, but they don't drive in the real world... the 5.3 seems to be the best HP / MPG combo.

the 6.2L however is wicked fast fun :)

I agree. GM's full-size SUV/trucks are heavy and require a lot of power just to get moving. I test drove a hybrid version and it was hard to keep it in hybrid mode while accelerating in the city. Any incline or a desire to move somewhat above slow would result in the engine starting and work harder than a non-hybrid would.

With my 09 Yukon XL Denali with the 6.2L and AWD it averages about 14mpg in the city. It doesn't take much gas pedal movement to keep up with traffic. However flooring it a few times will make the gas mileage drop but it also shocks the crap out of people since it can out accelerate most normal sedans and even a few performance ones. Mountain grades are not an issue.

On the highway I averaged 17-20mpg cruising at 75mph. 17 was into a strong headwind, 20 was actually around steep mountain grades.

I'm going to try to take the roof rails off on our next trip. I don't expect much gain though since you are basically driving a brick aerodynamic-wise to start with.
 

llllljrlllll

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I have HP tuners and to me it wasn't that hard. I would bump up the % a little, then calculate the MPG. I was also data logging at the same time.
BC is it possible to explain how you I bumped up the % for the V4 mode, I know that this is probably asking to much, how about a tutorial for noobs like myself, or maybe things that all of us can do to attain the same results as you.

---------- Post added at 12:10 AM ---------- Previous post was at 12:07 AM ----------

I have HP tuners and to me it wasn't that hard. I would bump up the % a little, then calculate the MPG. I was also data logging at the same time.
BC how did you bump up the % for the V4 mode, is it possible, maybe to write a tutorial or suggestions that we all can do, to have the same results as you
 

BC Lightning

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BC is it possible to explain how you I bumped up the % for the V4 mode, I know that this is probably asking to much, how about a tutorial for noobs like myself, or maybe things that all of us can do to attain the same results as you.


You have to either take it to a shop to tune it, or you have to buy the tuning software. I tune all of my vehicles so I bought HP Tuners. I looked into EFI Live but I dont like that its a hand held flasher. HP Tuners is a better tuner IMO. Data logging is the key!!!

There is a value for displacement on demand and has a throttle %. I would bump up the throttle % so that V4 mode would kick in if I use say less than 40% throttle. I calculate my mpg until I felt like it was the most I would get

I just bought a wideband so I'm going to hook it up and check the air/fuel ratio while I data log and see if I can bump up the timing a little more
 
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llllljrlllll

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thanks for answering my post, i guess you need to have some knowledge on how to tune a vehicle, are there are any places that you would recommend that do that type of jobs in your neck of the woods.
 

BC Lightning

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thanks for answering my post, i guess you need to have some knowledge on how to tune a vehicle, are there are any places that you would recommend that do that type of jobs in your neck of the woods.


There are a few shops here in Dallas that will tune, Black Bear is a Supporting Vendor here.

I just got on the forums and researched researched researched before I started tuning myself.
 

wba1

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My MPG

Got my 2010 Yukon Hybrid in late July. After several months I'm getting 21.2 MPG overall. On a trip from LA to Vegas, I got 24.8 MPG for that stretch. Around town getting right at 21. The eco meter is a good help to efficient driving. Thru about 8,000 miles everything is working properly. I'm quite pleased with my car. Looking forward to see what mileage I get when I tow a trailer.
 

sbhva

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I don't own a NNBS vehicle yet, but I did rent a 2010 Tahoe LT this fall for a trip to Wyoming. In 2 weeks I put on about 4,000 miles. I kept track of miles and gas purchased and "did the math". The truck averaged 19.5 mpg overall (5.3 engine). Roads ran the gamut from Interstate highways at 75 mph to unpaved two tracks in 4wd mode at less then 5 mph.
 

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