I have a 97 extended cab with 8 foot box with 5 speed manuel. Not pulling anything I am getting 15 to 16mpg, in the summer I got around 18, is this normal? I have always had a topper that sticks up about a foot or so on it.
This is highway driving at about 75 mph.
Matador

 

Sounds right to me. If you want better mileage just slow down, but don't be late for dinner!

 

I'm down 2 mpg already from 20. and it hasn't got below 0 yet.

If you are out around Bismark I would guess you will see -40 some day.

I went to school several days out there in -35 to -40 weather when I was a kid.



good luck

 

Man you guys are quick! I am from the Fargo area. You are doing good wings if you are getting 20 with a dually with 4.10 gears!

What speed are youdriving?

 

I'm averaging 18 to 18.5 with mine. Half ex-way and half open hwy. It hasn't dropped for the winter yet but I'm expecting it

 

What speed you drivin Hemicat?

 

E-ways 70-75 and open hwy 55-60. We have a lot of mountains out here too.

 

My timing is set factory. Some say advancing the timing will help some. What do you guys think?

 

It brought mine up a solid 1.5 mpg overall.

 

You could probably get better mileage by using Cenex fuel, availible all over ND.
Cenex doesn't use a winter #1/#2 blend that reduces power and mileage but rather adds anti-gel.

 

I was wondering about that? Fleet farm here in fargo I think maybe carries what you are talking about. It is supposed to be some highly refined diesel fuel and still carries the lubricity of #2 is what they said but still good to I think 30 below. I am going to check with Cenex and ask them about that. I have been filling up at stamart where you have to blend it yourself, which I dont like having to do.

Thanks for you reply,

 

Up here the winter mix of fuel is good for at least a 1.5 MPG drop. I do add a fuel additive to boost the mileage a bit, but it seems to affect the summer blends more. I use the stuff Piers sell, the Lubcorp performance additive. In the summer it gives me another 1 - 1.5 MPG. In the winter it drops the same amount as without so down 1 - 1.5 MPG. The idling time (I have high idle) for warm up and working in the truck on site takes that down even further.

On average in the summer I run about 18.5 - 19 MPG on the highway (~120 - 125 Kph / or 75 - 78 mph freeway and around 55-65 mph on the smaller highways.

J-eh