Need better fuel mileage

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Nate Dearth

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85
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85 k30 with smallblock 400 destroyed to a 377 and 4.10 gears with 8 inch lift on 38 inch pitbulls. Currently gets 9 to 10 mpg but I need to get better than that. Was wondering how much of an impact changing to 3.73 gears and maybe going a little smaller of a tire would do. Maybe 35s. Any suggestions?
 

Honky Kong jr

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85 k30 with smallblock 400 destroyed to a 377 and 4.10 gears with 8 inch lift on 38 inch pitbulls. Currently gets 9 to 10 mpg but I need to get better than that. Was wondering how much of an impact changing to 3.73 gears and maybe going a little smaller of a tire would do. Maybe 35s. Any suggestions?
That will cause you to use the go pedal a bit more to get that heavy som bitch moving. With all your fuel mileage killing variables 9-10 ain't bad. Other then a cost of going to a 4L80 and fuel injection that is or even a 6L80.
 

smoothandlow84

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Great fuel mileage and squares.....not common. 9-10mpg with your setup sounds about right
 

theblindchicken

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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.
 

Affende

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my 84 3+3 454 + sm465+ 208 .... 7MPG with the welder and gear in the truck .... downhill .... with a tail wind.

ill be moving to MPI next year.
 

theblindchicken

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my 84 3+3 454 + sm465+ 208 .... 7MPG with the welder and gear in the truck .... downhill .... with a tail wind.

ill be moving to MPI next year.

Engine off and trans in neutral too? Just bump start her every time you hit the bottom of the hill.
 

74 Shortbed

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My 73 dually with a big block got 8mpg uphill or downhill towing or empty when I got it, a little tuning and a GearVendors overdrive running empty at 78-80mph under "ideal weather conditions" I managed almost 15mpg, towing the boat with fuel and tools and crap I got 14mpg, with a 11 1/2" self contained camper on it I got 9mpg..

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Honky Kong jr

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My 73 dually with a big block got 8mpg uphill or downhill towing or empty when I got it, a little tuning and a GearVendors overdrive running empty at 78-80mph under "ideal weather conditions" I managed almost 15mpg, towing the boat with fuel and tools and crap I got 14mpg, with a 11 1/2" self contained camper on it I got 9mpg..

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Well lay tee dah lol :rotflmao:my pos 2015 f250 extended cab utility body with a 6.2 6spd auto gets 11.9mpg. Lol so op should be happy as a pig in **** with what he is getting.
 

74 Shortbed

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Well lay tee dah lol :rotflmao:my pos 2015 f250 extended cab utility body with a 6.2 6spd auto gets 11.9mpg. Lol so op should be happy as a pig in **** with what he is getting.
:happy175::happy175::rotflmao::rotflmao::laughing1::laughing1:
 

theblindchicken

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Well lay tee dah lol :rotflmao:my pos 2015 f250 extended cab utility body with a 6.2 6spd auto gets 11.9mpg. Lol so op should be happy as a pig in **** with what he is getting.

If you stopped towing the ford around, you might actually get some decent mileage for once!!!! :crazy::happy175:
 

Honky Kong jr

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If you stopped towing the ford around, you might actually get some decent mileage for once!!!! :crazy::happy175:
Lol it ain't my fuel card I just keep filling it up. It's funny I'm die hard Chevy but across my driveway sits 2 Edges an explorer and an f250. My truck is in the garage and there is a 97 oil leaker lumina with less then 30k on it sitting here too.
 

75Monza

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I got spoiled with the mileage my 99 cummins got, it was a 3/4 ton long bed quad cab slightly tweeked 24v, on the highway I got 22, towing got 14. Often ponder putting a 12v in my square after remembering why it came with dual tanks, lol...only briefly until I picture how heavy that would make the front of my truck. The Square is my favorite truck style, so I just totally ignore how much fuel I put in it and try to offset that amount driving my toy Metro around at 52mpg.
 

rt66paul

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yeppers. Just be glad it is not a big block Suburban. If I lifted it for monster tires with a big roof rack on Calif gas, I would get maybe 4 mpg..............
 

roadracerga

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85 k30 with smallblock 400 destroyed to a 377 and 4.10 gears with 8 inch lift on 38 inch pitbulls. Currently gets 9 to 10 mpg but I need to get better than that. Was wondering how much of an impact changing to 3.73 gears and maybe going a little smaller of a tire would do. Maybe 35s. Any suggestions?
 

roadracerga

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ga
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charles
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1980
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350
Big tires are a killer dropping down tire size will also decrease the rolling wait that will help with your mileage anything bigger than 33 just gonna hurt you 38 you're just tough to get better than 10
 

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