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I'm with Bob on much of my driving tactics except Semi drafting. Yes, it works but the safety concerns FAR outweigh any fuel savings. Besides, I live in Utah. If I drive that close behind a semi I can't enjoy the mountain views. :)

My current lifetime average is 26.8 mpg with my best tank being awfully close to 29 mpg. These numbers are based on actual miles divided by gallons pumped. Is 28 mpg possible? Absolutely, on warm summer days with cooperative stoplights. (Round trips with uphill and downhill in both directions)

My worst tank was when I tried "spirited" driving 80+ mph on the highway and WOT (Wide Open Throttle) from the stoplights. It still turned a respectable 21.9 mpg.

As far as the on-board computer goes, it's about 0.7 mpg optimistic. However, on those tanks where I get above 28 mpg the computer becomes a little more accurate (0.4 - 0.6 mpg optimistic). Perhaps even the computer has a hard time believing that this 2-ton 6-cylinder AWD can get that kind of fuel economy.

Cheers!

http://ecomodder.com/forum/em-fuel-log.php?vehicleid=4712
 

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That is interesting. What I seems to see is 22-25mpg on HW reported here. You report 27-29mpg. You must use different fuel than rest of us.
 

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Nope, US gallons from the local Chevron here in Utah (91 octane, weights and measures cert is current). The reported averages are combined highway and city (approx. 97% highway 3% city)

The trick is, high pressure LRR (low rolling resistance) tires, a blocked front grille and no roof rack (to improve aerodynamics) full synthetic oil in the engine and differentials, and a VERY light foot on the accelerator.

There are a few other tricks but the effectiveness has been marginal and not worth mentioning here.

Few people go to these extremes in order to get this kind of fuel economy. I just thought that I would chime in on this forum to let others know the possibilities, even if they're not willing to go to the same extreme.

If anyone else has other ideas that might improve mileage I'd be glad to hear them.
 

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08 limited

since having the transmission cooler installed and seating the dampner properly, up to 23.9 driving 75-80 on highway road trips.

average 18+ for combined (never below except some rare circumstances with no issues).

same mpg that my friend gets in his V6 accord.
Back from the grave.

Just took a 125 mile trip to VA Beach. Did not exceed 70 at any point and enjoyed the lower speed limits where 55 was permissable at times. 4 passengers, a dog, and cargo onboard with A/C running. Tires at 35 psi all the way around. E15 used which should hurt mpg over 93 octane. Averaged 25.2 mpg on the EZ30R. I am impressed. I also own a gen 2 Prius and Jetta TDI so I am conditioned to driving to get mpg.
 

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I have an 08 limited, I'd say maybe 20-22 freeway on cruize at 70 and 15 in town and about 10 in the mountains. My other car is a fusion hybrid and I get 35mpg average always so it's not like I'm rodding the crap out of this thing. When I picked this up in Portland my wife drove her Honda Element and I drove the Tribeca we filled up at the same station when we left. Followed each other all the way back and filled up when we came off the freeway and were within 50 cents of each other after a 3 hour drive. The Elements are rated at 20 mpg average and they don't get that. So if you guys are getting 24 plus do you only drive downhill ;)
 

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Nope, US gallons from the local Chevron here in Utah (91 octane, weights and measures cert is current). The reported averages are combined highway and city (approx. 97% highway 3% city)

The trick is, high pressure LRR (low rolling resistance) tires, a blocked front grille and no roof rack (to improve aerodynamics) full synthetic oil in the engine and differentials, and a VERY light foot on the accelerator.

There are a few other tricks but the effectiveness has been marginal and not worth mentioning here.

Few people go to these extremes in order to get this kind of fuel economy. I just thought that I would chime in on this forum to let others know the possibilities, even if they're not willing to go to the same extreme.

If anyone else has other ideas that might improve mileage I'd be glad to hear them.
I have done some of what you have with not near the mileage. I removed the roof rack and run synthetic in everything. Blocked off the air inlets on the wings on both sides of the center grill and the openings beside the fog lights. Did not do the center grill, did you? I also used aluminum tape to block air going anywhere but through the radiator. Another thing I did which helped is a set of forged BBS wheels off an sti which dropped a huge amount of rotational weight. It's too late to get the LRR tires as I put Continental extreme contacts on when I changed wheels. I do run 46 psi cold pressures in the tires. I log every fill up and am usually in the low 20's for mileage with 50/50 split most of the time which hurts I know, but I would never see your kind of mileage even 100% hwy. I do know higher elevations give better mileage because of the thinner air and thus lower drag. I always got my best mileage on bike trips out to Colorado when I was in state. I also forgot to mention I run a K&N air filter and I modified the top panel with the slots to provide outside air to the airbag inlet. Stock the air had to go through the slots and turn 90 degrees to get to the air inlet. I blocked those off and opened the ones directly in front of the air box inlet. I did notice slightly cooler ait's after doing that. I think insulating the airbox and piping would reduce it even further.
 
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