MPG DOESN'T ADD UP
Thread Starter
|
Elder User
Joined: Jun 2011
Posts: 930
Likes: 0
From: Los Angeles
MPG DOESN'T ADD UP
Ok so I have a 02 250 SD short box crew cab and my trip computer is telling me I only get 233 miles till empty right after a fill up which with a 29 gallon tank thats 8.03 MPG. I drive about 75-25 streets vs Highway and dont drive it hard.
Why are soo many getting over 10MPG?? Someone told me they get atleast 300 miles a tank. What am I doing wrong?? Or can the trip computer be wrong?
Why are soo many getting over 10MPG?? Someone told me they get atleast 300 miles a tank. What am I doing wrong?? Or can the trip computer be wrong?
Mountain Pass
Joined: Jan 2011
Posts: 132
Likes: 5
From: Monroe, NC
After reading a post on another thread here, I'm going to check my MPG next time using a GPS to determine my milage vs the odometer reading. With the larger tires you my want to do the same to get an accurate calculation.
Mountain Pass
Joined: Jan 2011
Posts: 132
Likes: 5
From: Monroe, NC
Your stock tire size was probably 265/75/R16 (30") or smaller.
Current tire size 305/75/R16 (34")
Your odometer (if it has not already been re-calculated for 34" tires) would read fewer miles with a set of 305/75/ R16 tires.
A gps will give you a more accurate milage number from point "A" to point "B" to divide the gallons consumed into. Effectively your mpg should go up.
I don't see much advantage in running your tank "empty" to check your mpg. Consuming 3/4 take should be good enough.
Current tire size 305/75/R16 (34")
Your odometer (if it has not already been re-calculated for 34" tires) would read fewer miles with a set of 305/75/ R16 tires.
A gps will give you a more accurate milage number from point "A" to point "B" to divide the gallons consumed into. Effectively your mpg should go up.
I don't see much advantage in running your tank "empty" to check your mpg. Consuming 3/4 take should be good enough.
Thread Starter
|
Elder User
Joined: Jun 2011
Posts: 930
Likes: 0
From: Los Angeles
Your stock tire size was probably 265/75/R16 (30") or smaller.
Current tire size 305/75/R16 (34")
Your odometer (if it has not already been re-calculated for 34" tires) would read fewer miles with a set of 305/75/ R16 tires.
A gps will give you a more accurate milage number from point "A" to point "B" to divide the gallons consumed into. Effectively your mpg should go up.
I don't see much advantage in running your tank "empty" to check your mpg. Consuming 3/4 take should be good enough.
Current tire size 305/75/R16 (34")
Your odometer (if it has not already been re-calculated for 34" tires) would read fewer miles with a set of 305/75/ R16 tires.
A gps will give you a more accurate milage number from point "A" to point "B" to divide the gallons consumed into. Effectively your mpg should go up.
I don't see much advantage in running your tank "empty" to check your mpg. Consuming 3/4 take should be good enough.
Mountain Pass
Joined: Jan 2011
Posts: 132
Likes: 5
From: Monroe, NC
Then your gas milage sucks! lol!
Trending Topics
Thread Starter
|
Elder User
Joined: Jun 2011
Posts: 930
Likes: 0
From: Los Angeles
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Moderator
Joined: May 2004
Posts: 6,510
Likes: 904
From: Home Base Nebraska
Some things to think about; You probably have 3.73 gears and the stock tires for a F250 were 235/85/16 so having 305 tires your finale gear ratio is way to high causing your truck to work harder burning more fuel.
When I was still in business one of the general contractors I worked with had a F250 SC V10 with 3.73 gears and running with a light load would never get the mileage I was getting with my F350 CC with utility box, 4.30 gears loaded to almost max GVW 24/7. I always got 9.5 to 11 in the summer (winter I let it run to keep warm) depending if I was pulling one of my trailers. Changing the final gear ratio always changes something else good or bad in your case bad.
Denny
When I was still in business one of the general contractors I worked with had a F250 SC V10 with 3.73 gears and running with a light load would never get the mileage I was getting with my F350 CC with utility box, 4.30 gears loaded to almost max GVW 24/7. I always got 9.5 to 11 in the summer (winter I let it run to keep warm) depending if I was pulling one of my trailers. Changing the final gear ratio always changes something else good or bad in your case bad.
Denny
Cargo Master
Joined: Sep 2007
Posts: 2,624
Likes: 7
From: OR and UT
Exactly. Bigger tires = more throttle to get her rolling in traffic. City driving MPG will suck accordingly.
Mountain Pass
Joined: Oct 2007
Posts: 185
Likes: 1
First of all I wouldn't use a computer prediction of how many miles I might get out of a tank to calculate my mileage. I would do it the way we used to do it before computers. Fill up and set your trip meter. Next time you fill up divide the trip meter miles by the number of gallons you put in at that fillup to get your miles per gallon. Of course if your odometer is not accurate because of tire size you won't get a good number. Use your GPS to figure how far it's off and factor that into the calculation.
Posting Guru
Joined: Mar 2005
Posts: 2,060
Likes: 7
From: Burnsville, MN
Also, if you want to check the accuracy of your speedometer directly, just clock the elapsed time between mile markers on a stretch of interstate. It will take exactly 60 seconds if you hold 60 mph.
Cargo Master
Joined: Jun 2011
Posts: 2,272
Likes: 208
From: Cincy area
I would definately not run the truck out of fuel. Ive been trying to work on mileage lately myself. Just use the trucks computer to help and not rely on it solely. I use it as a challenge to see what kind of numbers I get and in doing that I find myself driving like a grandpa and feel guilty when I have to use all the motor. Im constantly looking down at it and it helps atleast to save fuel whether its accurate or not. Do it by hand and itll be better. Keep her tuned up and its all you can do.
FTE Leadership Emeritus
Joined: Jul 2002
Posts: 42,561
Likes: 422
From: Long Island USA
I don't know if it was mentioned, but the 29 gallon tank, when the low fuel light comes on, usually only takes 24 gallons, at least it does for me.
The best way to check MPGs is record the miles, fill the tank, drive until it's low enough you care, and then fill again. Divide miles by how many gallons to fill.
It would be best if you use the same gas station, same pump, but not entirely necessary.
And, of course, like already said, check your actual miles with a GPS versus the odometer.
The best way to check MPGs is record the miles, fill the tank, drive until it's low enough you care, and then fill again. Divide miles by how many gallons to fill.
It would be best if you use the same gas station, same pump, but not entirely necessary.
And, of course, like already said, check your actual miles with a GPS versus the odometer.
