MPG Question
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From: Topeka,ks
MPG Question
I have the 1986 Ford 250 xl reg cab 6.9 diesel what can I expect for fuel milage on the front and rear tank. I am talking about what I can expect out of each tank. I put 30 bucks in the front tank and got 70 miles right now and in was almost on full now its right over 25 tank any help would be greatly appreatied. I run 55 to 60 mostly to work about 20 miles round trip. The tack sits at about 2500 at 60 does that sound right to u guys. have no clue what gears I have maybe u guys can tell me
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Ford Axle Code Chart .: Articles Here is a link to an axle chart. Look at the axle code on your drivers door sticker and compare to the chart (ignore where it says 1991).
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Can you clarify? Do you have 3.55 or 4.10 gears?
3.55 would probably give better MPG. However whatever you have it would cost a lot of $ to change as you would have to change front and rear axle ratios at the same time.
There is info here somewhere on the front and rear tank sizes but I can`t remember what they are. I`m sure someone will know so that you can calculate the miles range for each tank.
As a rough guide, I have a `87 6.9, C6, 4.10 gears, stock tires and in normal driving I would get around 14mpg.
3.55 would probably give better MPG. However whatever you have it would cost a lot of $ to change as you would have to change front and rear axle ratios at the same time.
There is info here somewhere on the front and rear tank sizes but I can`t remember what they are. I`m sure someone will know so that you can calculate the miles range for each tank.
As a rough guide, I have a `87 6.9, C6, 4.10 gears, stock tires and in normal driving I would get around 14mpg.
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From: Topeka,ks
Ok sorry I have 355. But i do have a complete front end and a complete rearend. So which is better sounds like the 410 if u get 14. I have got about 10 mpg with the 355 so far and its almost empty now so I will maybe get 11 or 12 with the 355. And since I have a complete front and readend with 410 it won't cost me nothing but time. How do u like the 410 with your c6. Is yours 4 wheel or 2 wheel
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From: Charles Town, W bygod Va
You probably won't like 4.10's if you do much highway driving, but if most of your driving is 55 and below they will help you get off the line better.
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Fleet Owner
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From: Mi'kma'ki
for 20 miles round trip,i wouldn't worry much.
however 11-12mpg isn't any good for a diesel pickup.you probably should start with an idi tune up,repacking front wheel bearings,brake inspection,front end alignment if required,and fresh gear lube.
but this could be normal too.i mean your just getting things warmed up nicely and then your at work lol.half your trip is spent getting the oils up to operating temp.
however 11-12mpg isn't any good for a diesel pickup.you probably should start with an idi tune up,repacking front wheel bearings,brake inspection,front end alignment if required,and fresh gear lube.
but this could be normal too.i mean your just getting things warmed up nicely and then your at work lol.half your trip is spent getting the oils up to operating temp.
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From: Topeka,ks
Ok now what I have is a 4 inch lift on it also and 33 x 12.50 16.5 rims they are alloys. Would that matter much. Cause the old truck I had is the motor I am using now and it did very good maybe 15 16 or better. So I no its not the motor. Plus evethang new but the injection pump. New injectors returns lift pump I mean all but the injection pump
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From: Mi'kma'ki
that explains it yes.
a lift = introduces more air flow under the truck where it's very dirty.air cannot flow smoothly over all that junk under there.
wider tires = increase rolling resistance requiring more energy from the engine.
c6 trans vs 4 speed = not much comparison here.the old school c6 is an energy hog in general.to top it off it's converter never locks.so these final 1:1 ratio gears are not created equal.you will get less FE with a c6 than you can with a manual.
for just 100 miles per week driving though,i wouldn't sweat it.the price difference between this and your last truck isn't all that much different.
a lift = introduces more air flow under the truck where it's very dirty.air cannot flow smoothly over all that junk under there.
wider tires = increase rolling resistance requiring more energy from the engine.
c6 trans vs 4 speed = not much comparison here.the old school c6 is an energy hog in general.to top it off it's converter never locks.so these final 1:1 ratio gears are not created equal.you will get less FE with a c6 than you can with a manual.
for just 100 miles per week driving though,i wouldn't sweat it.the price difference between this and your last truck isn't all that much different.
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