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95 4x4 ext. cab
95,000 miles
stock tires
3.55 gears
18-23 hwy , mosty 70-75 mph
13-16 hwy pulling a 4 horse aluminum trailer 60-75 mph
I always add a little outboard oil every fill up
 

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I've always thought the stock air dam doesn't go down enough to clear the air around the crossmembers and suspension.
My understanding is that it's main purpose is to create a low pressure area under the engine which will increase flow through the radiator.
 

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I always add a little outboard oil every fill up
I'm sure that is the reason you get such great mileage. 23 @ 70-75 just seems so unbelievable it must be due to a gasoline additive. Why not double it and get 26-29 mpg? Better yet, pure 2SO. Should get 100mpg or more!!! :hehe:
 

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never said the oil was the reason . Dont put words in my mouth . Thats what the calculator came up with . right or wrong, i really dont care if you believe it or not . some people act pretty tough behind a keyboard.
 

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It did. I guess I misunderstood jeepyr -- I thought he'd found/fashioned something a little taller. I've always thought the stock air dam doesn't go down enough to clear the air around the crossmembers and suspension. Kind of curious to A/B test it.
Idk how hard it would be to make fit but the new half ton ford trucks have a huge air dam, might check those out.
 

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never said the oil was the reason . Dont put words in my mouth . Thats what the calculator came up with . right or wrong, i really dont care if you believe it or not . some people act pretty tough behind a keyboard.
Then why mention it?

I'd say the same to your face. No, I don't believe anything over 20mpg (and that's tough to believe) driving at 75 or over 13 towing a horse trailer at 75 either. OK, I believe one way trips, like from the top of Eisenhower Pass to Denver.
 

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Re-read the post , 13-16 @ 60-75.
just got 14.5 at 65 to 70 yesterday .
To my face can be arranged.
 

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rebelrick, anyone can give a broad range. I get 10 to 15 mpg pulling trailers 3000 to 15,000 at 55-60 mph. Not much help to anyone. One time trips don't count in the grand scheme of things. The common tendency is to report the good ones and pretend it is the norm. I have a spreadsheet that covers the 27,500 miles I drove commercially last year. Annual mileage average is 12.57 My non-commercial mileage pulling my own trailers is a little better I think, but I don't track it. What is your average for the year?
 

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I just hook up my horse trailer up on weekends and pull 2 to 4 horses . most of the time i will check my mileage . maybe you should look in getting you a better truck and quite calling people liars .
 

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I just hook up my horse trailer up on weekends and pull 2 to 4 horses . most of the time i will check my mileage . maybe you should look in getting you a better truck and quite calling people liars .
OK hotshot, I believe you. 13-23 mpg driving 0-75. Got it.
 

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My trucks pretty heavy at 9500 lbs and usually has a 6500 lb trailer behind it when it's empty.
Last years running average, 12000 miles, all local roads here in central Ky was 12.7 mpg
Checked one truck only 120 mile round trip that averaged 14.7
Did a 250 mile round trip today with trucks first interstate miles since I've owned it, 80 miles of 75 mph interstate, haven't refueled to see what it averaged.
Tunes a little rich and have a couple of minor exhaust leaks at the manifold to head flange, once that's taken care of I'm hoping to see 16 mpg empty truck.
 

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My understanding is that it's main purpose is to create a low pressure area under the engine which will increase flow through the radiator.
It does do that as well, but it also cleans up the airflow across all the rough/weird surfaces of the underbody, and pushes the air out to the sides instead of going under. Most of the ecomodder-types consider a front air dam to be almost as good as a full belly pan (with obviously, a lot less maintenance issues). That's probably closer to the truth on vehicles _waaay_ shorter than my ECLB, though. Basically you add a couple square feet of frontal area in exchange for a pretty good reduction in drag.

I don't think adding an inch or two would significantly change mileage with regular (non-towing) driving, might even hurt, but I've been thinking about adding skirts to my 5er and wondering if clearing more air from the front might help as well.
 

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......wondering if clearing more air from the front might help as well.
That would be quite a trick considering the width of the 5er and the width of the top of the truck. Witness the pathetic wing on the roof approach.
 

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......wondering if clearing more air from the front might help as well.
That would be quite a trick considering the width of the 5er and the width of the top of the truck. Witness the pathetic wing on the roof approach.
Tracking fuel purchase and mileage over a long period of time would seem to be the only way to get close apprx of mileage. I once told a friend I would trailer a vehicle for fuel cost. Not that much distance but hard pull on a warm day.Filled before I left and when I got back. As I remember got better than 20mpg. What I didn't figure was temperature of fuel in the tank. It had gotten pretty warm. My buddy got away cheap. Seems you could possibly get better mpg in hot vs cold weather for that reason alone plus that would vary by how much is still in the tank.
 

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To the OP, mine is about the same. I tried to drive it like a grandpa for a week and really couldn't tell a difference. 14-15 mpg. 266k on factory injectors, so maybe they are a bit weak and could net me better mileage with a rebuild.

While I was a bit disappointed after calculating that first tank I got over it pretty quick. I like this truck more than any of the Jeeps, Trans ams, turbo street cars or other pick up trucks I've owned. I just fill it up and keep smiling lol.

Seems like the more I read, the more I realize that 20mpg isn't as common as I once thought it was.
 

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Trailer weight doesn't mean much in my opinion. I can tow a truck that weighs almost twice my camper and get worse with the giant sail of a camper.

I've never gotten below 16mpg empty on a stock truck, slightly modified trucks do a bit better.

An emtpy 2wd truck gets like 25 hwy so I seriously doubt your claims .
 

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Tracking fuel purchase and mileage over a long period of time would seem to be the only way to get close apprx of mileage.
As far as I'm concerned it is the only way. Too many variables affect one fillup to one fillup. Add to that the human tendency to round up, dismiss a poor tankful mpg, plus brag about how great your engine performs and a truck that really only is getting 13 all of a sudden is reported at 15 or 16 while towing. There is a truck stop in MT where the pumps are on a slope. I once filled up there going up slope, then since there wasn't any traffic, did a u-turn and filled up on the down slope side of the pump. A little over 2 gallons more was added. So if I had towed a trailer 300 miles and put 20 gallons in the result would be 15mpg, a number I see frequently in mpg threads. However, 300 divided by 22 gives 13.6, which doesn't appear to be a brag about number. Tow that trailer 2000 miles, then you know what kind of mpg you are getting. Then round up to the nearest whole number, add one or two, and post it on a thread. Almost everyone does.
 

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My 03 ccsb 4x4 with a 6 speed and 4.10s got 15-17mpg empty. The 17 was highway but staying between 68-72mph. All stock except for some tow mode mod. I just drove by the gas station the other day and diesel is 90 cents more a gallon. Thinking about going gas for the next truck. It doesn't seem like the new ones are getting that great of mileage either.
 

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The true difference is towing. I get the same maybe a little better than my dad's 5.3 V8 chevy.

Towing I get more than double what he does, and I don't have to watch coolant temp on hills.

For a daily driver that tows a camper once in a while and goes to home Depot I would get a new gas truck, but I'm not paying 40 grand. Old truck for me.
 

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The true difference is towing. .
agree a buddy has a chevy gas half ton and gets 16-18mpg. he hooked to a goose neck cattle trailer hauled some loads and got 8mpg and had no power doing it. if you are going to pull full time you need a diesel or a big gas engine. the big gas will still get around 8mpg.
 
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