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Discussion Starter · #1 ·
So, I have a 99 silverado. It's sitting on 38" tires. It's my daily driver as well. I was wondering if there were any fairly inexpensive mods I might be able to do to optimize fuel mileage even better? I believe I'm getting about 14mpg at the present moment. I have a hypertech programmer, as well as a cold air intake.

Anything else I might be able to do?

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boogity boogity
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Get rid of the 38's and if your getting 14mpg you should be playing the lottery.
 

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Discussion Starter · #3 ·
Get rid of the 38's and if your getting 14mpg you should be playing the lottery.
Lol. That really isn't bad.. comparing to other vehicles with the 5.3.. like my grandparents tahoe, that gets like 16

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What gears do you have?
 

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Better gears will help you. Those are some big heavy tires to get rolling
 

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on 33's with 3:73 gears, 220 cam, heads, FBO, and 91 nelsons tune along with 3200 stall. i would get 21-22 highway and 15-16 around town if i stayed outa it
 

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Discussion Starter · #9 ·
on 33's with 3:73 gears, 220 cam, heads, FBO, and 91 nelsons tune along with 3200 stall. i would get 21-22 highway and 15-16 around town if i stayed outa it
Damn.. 3200 stall?

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boogity boogity
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Lol. That really isn't bad.. comparing to other vehicles with the 5.3.. like my grandparents tahoe, that gets like 16

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I'm saying your lucky to get 14. With 4.88's and 35's I could pull 12-13 if I was lucky and there was no wind.
 

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Discussion Starter · #11 ·
I'm saying your lucky to get 14. With 4.88's and 35's I could pull 12-13 if I was lucky and there was no wind.
Yea, lol. I hate my small ass gas tank.. I always think she's a gas guzzler, but then I remember it's about a 16 gallon tank

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Discussion Starter · #13 ·
Better gears will help you. Those are some big heavy tires to get rolling
But again, yeah, she's regeared... I can be goin 45mph and gun er and she won't shift into OD until it's at like 5200rpm haha

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Have 4.88s and 35s and 22x14s and I get 13 if I'm lucky. Also have 3k stall, built tranny, headers and what not. But there's no way you're gettin 14mpg with 38s
 

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Have 4.88s and 35s and 22x14s and I get 13 if I'm lucky. Also have 3k stall, built tranny, headers and what not. But there's no way you're gettin 14mpg with 38s
Some of it could also be your tire/rim combo... 22"S x14 is heavy! plus the tires are gunna way a tone as well.
 

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Discussion Starter · #17 ·
Have 4.88s and 35s and 22x14s and I get 13 if I'm lucky. Also have 3k stall, built tranny, headers and what not. But there's no way you're gettin 14mpg with 38s
Also, it depends on your tires I guess too. How much resistance they have. (Loudness) I have Dick Cepek mud country and they're a fairly quiet tire.

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Ummm idk bout all that? i do know theres a video and dude swapped from stockers to his 20" and 35s and it was like 30-40 hp diff. Its rotating mass.
 

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A guy on youtube had a set of 20" rims with 35" tires and he dynoed them, changed to his stock rims "m 17s and stock tires and the differance was like 47 HP to the wheels i belive it was. Basically the heavy ass rim and tire combo robs Power.
 
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