Need better fuel mileage

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K5freak

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350 th350 203 with 35s and 3.73s my k5 gets 6 on a good day..... If you're worried about fuel milage I would suggest you sell your square to somebody here who will enjoy it and not stress on fuel milage
 

PrairieDrifter

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350 th350 203 with 35s and 3.73s my k5 gets 6 on a good day..... If you're worried about fuel milage I would suggest you sell your square to somebody here who will enjoy it and not stress on fuel milage

I think you might need a tune if you're getting 6mpg with a small block in a blazer lol
 

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I'd be happy with 9-10 consistent.

With 4.10's, th350, np203, and 35's under a 4-5" lift was only giving me maybe 8 mpg. But could be the difference in the drivetrain and the tune of the engine as well.

With 3.08, mildly built 350, th350, np203 concverted to part time with lock out hubs and 35's i get anywhere between 7 and 9 MPG. And that is driving it very easy. The speedometer and sensor are electric and are calibrated Hardly ever go over 55 because of back road driving and hills. Iam considering swaping to 4:10 gears. My thought is more torque for the hills so im not into the fuel as much and maybe get a little better MPG. My problem is the single 16 gallon fuel tank. I have to plan road trips via gas stations, lol.
 

HotRodPC

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I sure hope I get 9-10mpg in my K10/20.

If you don't like that 9-10, you could always convert to LS, 6.2 Diesel, or another diesel breed.

What kind of mpg are looking to get?
 
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HotRodPC

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That took care of that. I don't think you could have offended the new guy any worse than that. He won't be back now for damn sure.
 

CSFJ

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That took care of that. I don't think you could have offended the new guy any worse than that. He won't be back now for damn sure.

Lol. Couldn't resist. I think it should be the de facto response to anyone whining about mpg while driving these trucks.
 

74 Shortbed

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That took care of that. I don't think you could have offended the new guy any worse than that. He won't be back now for damn sure.
It is funny as hell though..:rotflmao:
 

yevgenievich

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I get about 37mpg on a daily drive to work.

That is until I get in the suburban. 10mpg mixed city driving. Stock 4x4 3/4 ton.
 

HotRodPC

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I get about 37mpg on a daily drive to work.

That is until I get in the suburban. 10mpg mixed city driving. Stock 4x4 3/4 ton.
You're also TBI. And probably have an OD too.
 

Green79Scottsdale

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I get 10mpg with my stock 400/TH400/3.73 combo. I must not be doing to bad?
 

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You're also TBI. And probably have an OD too.
About 13 on the mostly highway driving. OD helps some, but heavy 4l80e, 4x4 and 14 bolt are a negative for mpg
 

HotRodPC

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About 13 on the mostly highway driving. OD helps some, but heavy 4l80e, 4x4 and 14 bolt are a negative for mpg
But the TBI helps as well the OD if you have 4.10's or 3.73s helps quite a bit if it's getting you in the sweet spot at your cruise speed and you have lock up too. With my carbed 454, NO OD Turbo 400, No Lock up, the best I got was 13.2 and that was with an accurate odo and speedo so it's a fact, not wishful thinking. I was shocked. But I also set the cruise control at 65 mph on relatively flat drive and no wind to speak of that day. Set the Cruise at 70 mph on the way home, it got 11.5 mpg. This was an empty C20 pick up with 3.21 rear gears in the Full Float. Obviously the 65 mph was the sweet spot for that truck, gear ratio and no OD. Around town, 7.5 - 8 mpg.
 

87ChevyR10

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Gas mileage has been on my mind lately, too. I think I get about 12 MPG. I've been tossing around the idea of selling my truck and getting a more fuel efficient vehicle. Although, I really don't like my options for the price of vehicle I can afford. I really don't want to cram my 6 foot 2 body in a Smart FourTwo Passion nor would I want to be seen with one (shudders).

Basically, it's like this. On average, I drive 150 miles a week. Currently, gas is 2.15 per gallon; so, $34.4 to fill 16 gallons. This translates to needing to spend almost $27 per week to meet the 150 miles I drive. So on average, I'm spending about $1400 per year on gas or about $116 per month. Now, if I were to get a car which gets 30 miles per gallon, the costs drop a ton. That $1400 per year drops to $559 or $46 per month. After looking at the savings, the thought of a car payment doesn't feel so bad. However, I have yet to see a compact car which I like. The Mini Cooper Clubs look neat, The Fiesta is a no go (I had one for a while) and I wouldn't even touch a Chevy Sonic or a Fiat.

Personally, I'd like to stick with an older vehicle. I've always wanted a classic VW Bug. But, I doubt I'd fit too well.
 

yevgenievich

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Sonic worked out fine for me, but at this time my choice might be different. 4 years ago Sonic was as good as it gets for a small hatchback with space and some power, but they are behind the power game by now. Head room was one of the biggest factors for me, and 37mpg city does not hurt either. But I have been itching to sell it as well to get back in to the trans am for a daily driver.

We originally bought the Sonic when my daily was a 88 one ton dually with 454 and sm465 with 300k miles on them, later it was passed to relatives and recently we got it back again.
Gas mileage has been on my mind lately, too. I think I get about 12 MPG. I've been tossing around the idea of selling my truck and getting a more fuel efficient vehicle. Although, I really don't like my options for the price of vehicle I can afford. I really don't want to cram my 6 foot 2 body in a Smart FourTwo Passion nor would I want to be seen with one (shudders).

Basically, it's like this. On average, I drive 150 miles a week. Currently, gas is 2.15 per gallon; so, $34.4 to fill 16 gallons. This translates to needing to spend almost $27 per week to meet the 150 miles I drive. So on average, I'm spending about $1400 per year on gas or about $116 per month. Now, if I were to get a car which gets 30 miles per gallon, the costs drop a ton. That $1400 per year drops to $559 or $46 per month. After looking at the savings, the thought of a car payment doesn't feel so bad. However, I have yet to see a compact car which I like. The Mini Cooper Clubs look neat, The Fiesta is a no go (I had one for a while) and I wouldn't even touch a Chevy Sonic or a Fiat.

Personally, I'd like to stick with an older vehicle. I've always wanted a classic VW Bug. But, I doubt I'd fit too well.
 

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