help with mpg
Hotshot
Joined: Jul 2003
Posts: 12,177
Likes: 40
From: Newport, WA
We need WAY more info to help you out.
When was the air filter last changed? What air intake are you running (stock, aftermarket?)
When was the fuel filter last changed?
Tire size?
Gear ratio?
Stick or auto?
Any go-fast mods- tuner, big injectors, different turbo?
Are you getting good fuel?
Do you run bio?
Lots of things factor in to fuel mileage. Probably one of the biggest is that diesel likes to foam when you fill up, so often you don't get the tank truly full because there is a "head" of foam at the top of the tank, so when you calculate MPG you are way off. Also, never rely on the stock computer if you have one, they are well known for being inaccurate.
When was the air filter last changed? What air intake are you running (stock, aftermarket?)
When was the fuel filter last changed?
Tire size?
Gear ratio?
Stick or auto?
Any go-fast mods- tuner, big injectors, different turbo?
Are you getting good fuel?
Do you run bio?
Lots of things factor in to fuel mileage. Probably one of the biggest is that diesel likes to foam when you fill up, so often you don't get the tank truly full because there is a "head" of foam at the top of the tank, so when you calculate MPG you are way off. Also, never rely on the stock computer if you have one, they are well known for being inaccurate.
Posting Guru
Joined: Mar 2008
Posts: 1,104
Likes: 5
From: West Tx
I would ditch the K&N right away...don't want to kill your turbo. The additional rotational mass from the larger tires would hurt mpg, but not halve it... Has your mileage just recently dropped or has it been low for a while? Maybe your torque converter isn't locking...regearing may help too
Post Fiend
Joined: Apr 2007
Posts: 7,241
Likes: 1
From: Powder Springs, East TN
Agreed ditch the K&N and see if you can get the truck recalibrated. The lift and big tires will murder your MPG even more so if you have a heavy right foot. Check your turbo boots and such for leaks and also check for exhaust leaks around your up pipes both are MPG Killers.
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Token Redneck
Joined: Jun 2007
Posts: 9,331
Likes: 341
From: Breckenridge, TX
There's 5 mpg right there... regear it to 4.56s and you'll be much closer to where you were before you put on the meats.
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