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**LEEVON** · 04-24-2011, 07:41 PM

I was able to squeeze 20.1 mpg out of my '08 with AFM, mixed highway and city over an average of 500 miles. I never went over 2000 rpms, coasted down hills and just generally babied it and drove like a really old person. It was a really effort though, normal driving style yields 16.7 mpg over an average of about 10K miles.

What really kills me is how long the 4 cyl mode stays on. If you even sniff the gas pedal it goes back into 8 cyl...I'd like to get a tune to make this stay on longer and adjust the timing tables, TM, etc. At first I wasn't worried about mileage, but with the above results and gas prices I'm starting to rethink that approach.

Mykk it sounds like you've had some success, do you do any mail order tuning or just local?

04-24-2011, 07:41 PM	#40
LEEVON Registered User Join Date: Jul 2006 Location: Ozark, MO Posts: 4,887	Re: what are you guys getting for mpg? I was able to squeeze 20.1 mpg out of my '08 with AFM, mixed highway and city over an average of 500 miles. I never went over 2000 rpms, coasted down hills and just generally babied it and drove like a really old person. It was a really effort though, normal driving style yields 16.7 mpg over an average of about 10K miles. What really kills me is how long the 4 cyl mode stays on. If you even sniff the gas pedal it goes back into 8 cyl...I'd like to get a tune to make this stay on longer and adjust the timing tables, TM, etc. At first I wasn't worried about mileage, but with the above results and gas prices I'm starting to rethink that approach. Mykk it sounds like you've had some success, do you do any mail order tuning or just local? __________________ '20 Silverado Trail Boss ~ '17 Tahoe ~ '79 K15 Sierra Grande ~ '76 Blazer 2wd ~ '71 Cheyenne swb ~ '55 Pontiac Safari ~'50 3100 bagged ~ '80 Wife ~ Late model kids Last edited by LEEVON; 04-24-2011 at 07:42 PM.