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Discussion Starter #1
So ive noticed recently ive been getting bad mileage, about 15.5 MPG cruisen at 65-70 MPH, did i put in a bad batch of fuel? Anyone got ideas? My 2005 cummins got about 23-24 cruisen at the same speed, it had intake but thats the only real difference..:help
 

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I'd be tickled to get 15 mpg. Never achieved it. This isn't a cummins. It is a bigger engine and a v-8.
 

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I am getting 15 around town and 17-19 on the hwy depending on how heavy my foot is. I have AMSOIL front to back and use their fuel concentrate and their cetane booster in every tank of fuel.

If I can get you any information about the products above or anything else AMSOIL sells, just let me know.

Take care,
 

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How long has it been since you changed your fuel filter? A dirty fuel filter will decrease mileage.
 

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How long has it been since you changed your fuel filter? A dirty fuel filter will decrease mileage.
And your air filter, how many miles do you have?
 

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Discussion Starter #8
Truck has 186000 kms, which is about 111600 miles i think..havnt changed the fuel filter since i bought it with 174000 kms on it, ill look at the air filter today aswelll
 

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u must be joking............
 

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Change the fuel filter, air filter, and spin on tranny filter.
 

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I get about 15-16 around town!
Change your fuel filter. I change mine every time I change my oil.
 

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Discussion Starter #13
I guess ill have to do the fuel and oil filter tomorrow, ill check the air filter, changed the oil today but forgot to do the oil filter since im retarded
 

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I guess ill have to do the fuel and oil filter tomorrow, ill check the air filter, changed the oil today but forgot to do the oil filter since im retarded
What oil and filter are you running?
 

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Fuel mileage juts fell off the cliff

I get about 15-16 around town!
Change your fuel filter. I change mine every time I change my oil.
HELP!!!
I was getting 15-16 before last week.
This week...down to 10-11.
Fuel filter changed since last oil change. Oil life still has apprx 40% remaining. Air filter cleaned at last fuel filter change.:help
 

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HELP!!!
I was getting 15-16 before last week.
This week...down to 10-11.
Fuel filter changed since last oil change. Oil life still has apprx 40% remaining. Air filter cleaned at last fuel filter change.:help
Are you using a good additive? I am using the AMSOIL fuel concentrate and their cetane booster in every tank of fuel. I have seen a 2-3 mpg increase in my economy.

If I can get you any information about the products above or anything else AMSOIL offers, just let me know.

Take care,
 

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Only when I got ahold of some bad fuel. Don't use it on a regular basis.
 

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Only when I got ahold of some bad fuel. Don't use it on a regular basis.
You should consider it. Beyond he help with fuel economy, there isn't enough lubrication anymore in fuel, plus you want them to remain clean for the best performance.

Let me know if I can help you with anything.

Take care,
 
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