Seamus
Full Access Member
Hey guys,
New to the forum but not to GM trucks. I have had many Gm trucks over the years and remember when 13 mpg was average. My last truck of this generation was a 2007 Sierra CC 5.3 w/ 3:42 gears averaged 14-15 mpg. Sold it in 2012 and have since owned a 2014 Silverado CC 5.3 3.08, -2015 Sierra CC 5.3 3.42, -2015 Denali XL 6.2 3.23 and then a 2017 Denali 6.2 3.23. The Denali got impressive fuel mileage. 23 mpg on the highway. 21mpg driving aggressively. Florida is 80 mph all day on the Turnpike. Surprisingly the 5.3 6 speed in the new trucks gets less mpg than the 6.2 w/ the 8 speed.
I was really disappointed with the new generation trucks. Too long of a story but the seats and the ride were terrible. Many other issues also. I loved the older LS trucks and started my search going back. I found a 2013 suburban LTZ , white diamond, with heavy duty tow package and 3.42 gears, 2wd. Dealer serviced since new, insane service records. 94k on her. A great find. Just did a lot of serviceable items, belts, tensioners, pulley, synthetic fluids rear, trans and engine, new Michelin defender tires, spark plugs, wires, air filter, brake fluid flush, and all 4- o2 sensors.
I got 17.5 mpg driving her home 250 miles. Around town I am getting 14 mpg. Well after all my service and new tune up parts I figured I pick up a little mpg???.........Well I was wrong!! I am getting 17.6
I guess I have been spoiled with better mileage these last years in the new trucks. Hated the trucks but loved the mileage. I figured with the sticker stating 21 mpg maybe 19 mpg wasn't an unreasonable expectation?
I have read many are in the 17 mpg range? Am I correct? Anything I can do?
The trans although shifting well ,never seems to be in the right gear for my acceleration. I am considering a black bear tune to get better shifting and a little power but those of you that have it can I expect to gain any MPG or will I lose MPG?? I just want better drivability and MPG. Love the truck otherwise, very happy to be back in the saddle. Newer is not always better, lesson learned...expensive lesson.
What MPGs are the 2wd guys getting?
Sorry for the long story, thanks for your experience and help
New to the forum but not to GM trucks. I have had many Gm trucks over the years and remember when 13 mpg was average. My last truck of this generation was a 2007 Sierra CC 5.3 w/ 3:42 gears averaged 14-15 mpg. Sold it in 2012 and have since owned a 2014 Silverado CC 5.3 3.08, -2015 Sierra CC 5.3 3.42, -2015 Denali XL 6.2 3.23 and then a 2017 Denali 6.2 3.23. The Denali got impressive fuel mileage. 23 mpg on the highway. 21mpg driving aggressively. Florida is 80 mph all day on the Turnpike. Surprisingly the 5.3 6 speed in the new trucks gets less mpg than the 6.2 w/ the 8 speed.
I was really disappointed with the new generation trucks. Too long of a story but the seats and the ride were terrible. Many other issues also. I loved the older LS trucks and started my search going back. I found a 2013 suburban LTZ , white diamond, with heavy duty tow package and 3.42 gears, 2wd. Dealer serviced since new, insane service records. 94k on her. A great find. Just did a lot of serviceable items, belts, tensioners, pulley, synthetic fluids rear, trans and engine, new Michelin defender tires, spark plugs, wires, air filter, brake fluid flush, and all 4- o2 sensors.
I got 17.5 mpg driving her home 250 miles. Around town I am getting 14 mpg. Well after all my service and new tune up parts I figured I pick up a little mpg???.........Well I was wrong!! I am getting 17.6
I guess I have been spoiled with better mileage these last years in the new trucks. Hated the trucks but loved the mileage. I figured with the sticker stating 21 mpg maybe 19 mpg wasn't an unreasonable expectation?
I have read many are in the 17 mpg range? Am I correct? Anything I can do?
The trans although shifting well ,never seems to be in the right gear for my acceleration. I am considering a black bear tune to get better shifting and a little power but those of you that have it can I expect to gain any MPG or will I lose MPG?? I just want better drivability and MPG. Love the truck otherwise, very happy to be back in the saddle. Newer is not always better, lesson learned...expensive lesson.
What MPGs are the 2wd guys getting?
Sorry for the long story, thanks for your experience and help
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