chasing MPG's with 6.ol and 24's... 3.42/3.73? mods? cam? *what can be done*
12-05-2010, 09:56 PM
#11
Unless you run open loop in the tune, the pcm will still command 14.7. Trims will just keep it right at that. You can increase the timing in the cruise cells of the timing tables. 1850 at 70 is not lugging, and once you start increasing those cruise rpms, you are increasing consumption of fuel because of increased rpms. Of course there is a happy point in between a good cruise rpm vs pedal input, kpa, timing blah blah. A few degrees of timing can help, I just dont see you getting any better mileage with any other gear. THe wheels are killing it, not only because of static weight, but because of the increase rotational mass, there is your lug.
12-05-2010, 10:42 PM
#12
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Unless you run open loop in the tune, the pcm will still command 14.7. Trims will just keep it right at that. You can increase the timing in the cruise cells of the timing tables. 1850 at 70 is not lugging, and once you start increasing those cruise rpms, you are increasing consumption of fuel because of increased rpms. Of course there is a happy point in between a good cruise rpm vs pedal input, kpa, timing blah blah. A few degrees of timing can help, I just dont see you getting any better mileage with any other gear. THe wheels are killing it, not only because of static weight, but because of the increase rotational mass, there is your lug.
also i thought it was 1850@70 but it is not.. i checked it with a snap-on code reader and it is actually 1680rpm at 70mph with 3.42 gears and a 33.2" tall tire
and as far as the pcm commanding 14.7 i PERSONALLY witnessed RWTD putting that to 14.1 via HPT because of the fuel now having 10% ethanol so i am pretty sure a 15.1 can be achieved via HPT as well...
12-06-2010, 03:44 AM
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I got a cheap soft tonneau cover, helped a bit with mileage on the road and keeps stuff out of the wind and weather. Rolls up quickly when you need the bed. Also cleans up looks a bit imo. Getting females because of rims, debatable. Increasing mileage, ride quality, and peace of mind driving over bumps or parking in the ghetto with factory 17" wheels, certain 
12-06-2010, 07:56 AM
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I got a cheap soft tonneau cover, helped a bit with mileage on the road and keeps stuff out of the wind and weather. Rolls up quickly when you need the bed. Also cleans up looks a bit imo. Getting females because of rims, debatable. Increasing mileage, ride quality, and peace of mind driving over bumps or parking in the ghetto with factory 17" wheels, certain
not alot of difference other than the steering isn't spongy like it is with tall sidewalls
maybe but it makes you a better more attentive driver
why would you be parking in the ghetto? and if you were obviously you know people and they know you so they WILL not be messing with your ride
factory made 20" because even they know 17's are for import cars:nunchuk1:
12-06-2010, 02:05 PM
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maybe
not alot of difference other than the steering isn't spongy like it is with tall sidewalls
maybe but it makes you a better more attentive driver
why would you be parking in the ghetto? and if you were obviously you know people and they know you so they WILL not be messing with your ride
factory made 20" because even they know 17's are for import cars:nunchuk1:
not alot of difference other than the steering isn't spongy like it is with tall sidewalls
maybe but it makes you a better more attentive driver
why would you be parking in the ghetto? and if you were obviously you know people and they know you so they WILL not be messing with your ride
factory made 20" because even they know 17's are for import cars:nunchuk1:
12-06-2010, 06:55 PM
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why wouldn't gears help me? wouldn't they be making my load % less... causing better economy?
that is how my mind works atlease... and i'm looking for average not mpg@70
that is how my mind works atlease... and i'm looking for average not mpg@70
12-06-2010, 07:08 PM
#19
No. In my experience, the more RPMs the worse the gas mileage.
I just drove 560 miles roundtrip and averaged 14.5 mpg with the cruise set to 65.
The H/C, 4l80e (3600 stall - no effect on highway), 4.10s, and 285/60/18s (vs 255/70/16) reduced my highway gas mileage by 9 mpg. It might be 1-2 less than that actually due to summer vs winter blend gas.
I'm going to be changing up my setup in the next couple of months to get my gas mileage back, performance is the last thing on my mind nowadays. I don't know if I can get over 20 MPG with the 80e but I will try.
I just drove 560 miles roundtrip and averaged 14.5 mpg with the cruise set to 65.
The H/C, 4l80e (3600 stall - no effect on highway), 4.10s, and 285/60/18s (vs 255/70/16) reduced my highway gas mileage by 9 mpg. It might be 1-2 less than that actually due to summer vs winter blend gas.
I'm going to be changing up my setup in the next couple of months to get my gas mileage back, performance is the last thing on my mind nowadays. I don't know if I can get over 20 MPG with the 80e but I will try.
12-06-2010, 07:18 PM
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hmmm....... i'm confused...
being my truck is 5500ish lbs and i have 120ish lb wheels PER corner.... i'm sure its like pulling a trailer EVERYWHERE ALL THE TIME right? there for i am using (example purposes only) 15% throttle @ cruising speeds with 3.42 gears.... wouldn't 4.10 make it be less throttle %??? there for causing less fuel consumption???
i have READ ON THIS SITE WAY MORE THAN ONCE that people getting BETTER mpg's with a 4.10 compared to 3.73 ect....
i think if my truck was a regular cab with stock tires and never towed a "bigger" gear would hurt but being i have 450lbs of extra wheels and my truck being a crew cab and i pull a trailer with a 1000lb ATV very often that i think the 3.73/4.10 could only help my mpg's
am i wrong?
being my truck is 5500ish lbs and i have 120ish lb wheels PER corner.... i'm sure its like pulling a trailer EVERYWHERE ALL THE TIME right? there for i am using (example purposes only) 15% throttle @ cruising speeds with 3.42 gears.... wouldn't 4.10 make it be less throttle %??? there for causing less fuel consumption???
i have READ ON THIS SITE WAY MORE THAN ONCE that people getting BETTER mpg's with a 4.10 compared to 3.73 ect....
i think if my truck was a regular cab with stock tires and never towed a "bigger" gear would hurt but being i have 450lbs of extra wheels and my truck being a crew cab and i pull a trailer with a 1000lb ATV very often that i think the 3.73/4.10 could only help my mpg's
am i wrong?