Poor Fuel Economy 03' 5.3L
#12
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if ur on the interstate if u go 70mph slow down to 65mph they had that on the news a while back around here.. i know when i get off work at 2:30 in morning since there is no traffic mite meet one car once i get to the top of the mountain the speed limit is 65 and i usually set cruise at 50 or 55 lol
#13
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if ur on the interstate if u go 70mph slow down to 65mph they had that on the news a while back around here.. i know when i get off work at 2:30 in morning since there is no traffic mite meet one car once i get to the top of the mountain the speed limit is 65 and i usually set cruise at 50 or 55 lol
#17
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You can't just say a specific MPH to run at it depends on your effective gear ratio. I believe for optimal fuel economy the LS should be run between 1500 and 1800 rpm. For me that's between 60 and 70mph. I've netted over 23mpg with the 6.0 WITH my original 4.8 in the bed lol doing about 65 cruise over a 400 mile trip.
#18
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You can't just say a specific MPH to run at it depends on your effective gear ratio. I believe for optimal fuel economy the LS should be run between 1500 and 1800 rpm. For me that's between 60 and 70mph. I've netted over 23mpg with the 6.0 WITH my original 4.8 in the bed lol doing about 65 cruise over a 400 mile trip.
im turning 2150 at 70 with the 80E/3.42/28"
and it does pretty good..
i cant remember what my rpms are at 55 but ive hit some nice size hills and it didnt down shift or bog and i think i got into boost a time or two..
#19
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I know what your talking about... but most of the time when you hit a hill or something its goin to bog and downshift.. ive always "heard" that 1900 is the sweet spot for LS's..
im turning 2150 at 70 with the 80E/3.42/28"
and it does pretty good..
i cant remember what my rpms are at 55 but ive hit some nice size hills and it didnt down shift or bog and i think i got into boost a time or two..
im turning 2150 at 70 with the 80E/3.42/28"
and it does pretty good..
i cant remember what my rpms are at 55 but ive hit some nice size hills and it didnt down shift or bog and i think i got into boost a time or two..
#20
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I drove 1300 miles this weekend. Saturday we went to TN/KY and on the way up I got 12.5 on the highway. On the way back 11.7 granted I had some stuff in the bed. Several hundred pounds. Yesterday I went above Atlanta towing a Corvette that belongs to a friend. I got like 9.9 towing the trailer. That was running 75-80 the whole way on all trips. At that MPH it is turning close to 2500 rpm and rarely downshifted going up and down the hills. Any faster it would downshift to keep speed. That speed seemed to be the best speed to run.