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5.3 vs 6.2 mpg


mikern

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Posted

I checked the RPO codes, it's a 3.08 on mine. I'm going to drive a bit more aggressively this tank and see what the fuel econ averages out to. I have an open diff too. It may be worthwhile in a year or 2 to look into changing the gears. Ya know back a few years ago I had a z28 camaro Ls1 with 2.73 "highway gears." It couldn't pass a honda civic. :lol: but it got 21mpg! I looked high and low for a 3.42 car and when I finally found one in a salvage yard, I walked around the back to find the diff cover laying on the ground next to it. :( I guess cafe standards are the only reason they include these in these trucks?

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Posted

i don't believe the 6.2 can get 18mpg city. i find that almost impossible in true city driving.

 

driving as slow as i can from light to light i can get 16mpg. my real world 25 and 50 mile trips are more like 12-14 driving easy. if i'm driving without thinking its more like 11-13. i do true city driving with about 16 lights a day on my commute.

 

highway i can get 19-23 pretty easy doing 65-75.

Posted

I checked the RPO codes, it's a 3.08 on mine. I'm going to drive a bit more aggressively this tank and see what the fuel econ averages out to. I have an open diff too. It may be worthwhile in a year or 2 to look into changing the gears. Ya know back a few years ago I had a z28 camaro Ls1 with 2.73 "highway gears." It couldn't pass a honda civic. :lol: but it got 21mpg! I looked high and low for a 3.42 car and when I finally found one in a salvage yard, I walked around the back to find the diff cover laying on the ground next to it. :( I guess cafe standards are the only reason they include these in these trucks?

 

Yeah, your gears are why your 5.3 is so lazy. Going to the 3.42's would definitely make a world of difference. The 3.73's even more, but if you don't tow, or tow very little, the 42's are plenty good enough. It would have been nice to have a 6.2, but I'm happy. I couldn't pass up my truck for the price with all the extras it had.

 

I can definitely pass a Civic and quite a few other types too, and still get between 20-21 mpg! :)

Posted

Can I even tow with 3.08s? I'm getting worried about this now..

 

If the trailer isn't very heavy and the terrain isn't too hilly, I don't see why not.

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