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Does Anyone Get Good Gas Mileage Out of a 4.8L?

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Old 04-09-2011, 03:33 PM
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Default Does Anyone Get Good Gas Mileage Out of a 4.8L?

I get about 15-18mpg out of mine. Would a tune increasing spark advance help?

Mods are !cats, catback, and underdrive pulley. It also has 4.56 gears but it didnt seem to make any difference with the gas mileage.

Its a rclb 2wd weighing in aroud 4800 pounds.
Old 04-09-2011, 06:22 PM
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I am getting around 20 mixed driving.
Old 04-09-2011, 06:32 PM
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i had a 4.8 in my 2002 before my swap wasnt too bad but i get a round the same with my 6L as i did with a 4.8
Old 04-09-2011, 06:37 PM
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higher compression,5+ tire psi, tune, headers, cai, udp, efans, will all help..But as alot of other guys say the little 4.8 has to work alot harder (especially up hills) than a larger motor..My H/C gets 16 mixed..Which will get better with more fine tuning.....
Old 04-09-2011, 07:10 PM
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I got 20 mpg mixed driving before cd 3k stall and 456 gears now im getting around 17-18 mpg sometimes i get more out of her which still isnt bad for what i got.
Old 04-09-2011, 07:57 PM
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i get around 21mpg mixed with a tune, exhaust, and t-56 with 3.73s
Old 04-09-2011, 08:19 PM
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I also get 17-18 mixed driving with 4.11's and a 4000 converter on 87 octane.
Old 04-09-2011, 08:53 PM
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this makes me hate having the 5.3 im getting around 14 on a good day. wtf ?
Old 04-09-2011, 08:58 PM
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Originally Posted by Rhino79
I also get 17-18 mixed driving with 4.11's and a 4000 converter on 87 octane.
You're kidding, right? I have a very hard time believing that unless you drive 80% highway.


My bone stock 2wd ex cab with 3.42s and 4.8L got 18 mixed with about 75% highway.
Old 04-09-2011, 11:03 PM
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Originally Posted by KozzyJr
i had a 4.8 in my 2002 before my swap wasnt too bad but i get a round the same with my 6L as i did with a 4.8
yeah, thats whats annoying about the 4.8L, less power and same gas mileage as the 6L


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