Mileage...

[JyRO]

17,000 GCW, 3. 54 gears, 6-speed, tall 5'er. I try to run 68 mph. With EZ & 275's. I get a skosh under 11 mpg.



One thing that irks me, and I realize I'll get flamed for it, is when someone says something to the effect of, "I get X mpg no matter how I drive it. " What a crock (I think). I personally think that their vehicle must be driven similarly (erratically) from tank to tank.



If I drive conservatively, I can get nearly 20 m. p. g. city/highway, unloaded. If I drive spirited (which is considering a 7,200 lb truck), I get 16 - 17 mpg city/highway, unloaded. If I run a tank steady @ 65 mph on the interstate, I'd get 22 - 23 mpg, unloaded. My mileage definitly varies depending on the discipline of my right foot.



- JyRO

 

[klenger]

I think members also seem to post when they get their best milage, but seems to be interperted as average milage. I've gotten 20, but 17-18 is more usual unloaded. Towing is usually 10-11. Since I moved two weeks ago, my commute is now about 12 miles one way at 50 - 60 MPH with only a few lights. I expect to see some better milage at those speeds.

 

[RustyJC]

Originally posted by klenger

Since I moved two weeks ago... ...

Ken,



Are you in your new house?



Rusty

 

[Boldt's Wagon]

JyRO - Your post sounds exactly like what I get with a 18,000 gross fiver.



I have noticed that the boost (fuel consumption and power) is higher on cold start up until I get about 20 miles down the road. It takes some time to warm up the tires, wheel bearings, and that 140 weight grease in the rear end. Short trip commuting will never have the mileage of a long trip.

 

[pwr2tow]

I agree, but after getting flamed so many times I quit posting on mileage related threads.



See signature for mileage.



Ron

 

[HC]

Originally posted by JyRO

One thing that irks me, and I realize I'll get flamed for it, is when someone says something to the effect of, "I get X mpg no matter how I drive it. " What a crock (I think). I personally think that their vehicle must be driven similarly (erratically) from tank to tank.

- JyRO

Flame you? Not me - I agree with you completely! After over 128,000 miles of writing down the numbers at every fuel stop, many of those miles spent going back and forth over the same daily commute, I'll vouch that every minor thing [including the ones most people don't even notice] makes a difference. I can tell differences in mpg with <5 mph headwind or tailwind, wet pavement vs. dry, outdoor temperature, driving 3 mph slower, even number of orange barrels along my commute route (more barrels = longer slow drive through the construction zones = increased mileage, so more barrels = increased mpg). Carrying objects in the back instead of on the roof racks makes a difference, too.

 

[JyRO]

Oooops ... meant to reply, not start a new thread...

I must have started a new thread when I meant to just reply to THIS thread.



Ooops! Worked out OK I guess. Now, let me make sure I'm not starting a new post again, before I hit submit.



- JyRO

 

[klenger]

Rusty:



We moved in two weeks ago. Still trying to get settled. At least the truck and car fit in the garage. Still need to hook up the dump station and trailer 115v to the driveway. I'll post pics of the trailer in the driveway when I get it to the house.

 

[GAmes]

With a tall 5er speed makes ALL the difference in fuel economy due to a phenomenon known among attack helicopter pilots, and others, as flat plate drag. There is even an equation for it that I can not quote anymore, but essentially the drag increases exponentially with air speed. If I pull my 5er at 60 mph I average almost 13 mpg. If I increase the speed to 63 it drops to less than 11 mpg. What that comes to in $$$ and time is that for every 300 miles I travel I gain 15 minutes and use 4 more gallons of fuel, roughly $22 an hour. Since I'm retired time is free but fuel is not. I'll stick with 60 mph.

 

[Casey Balvert]

On a recent trip I noted a 2. 5 mpg decrease in fuel economy with an 8 mph increase in speed. If you are in a hurry be prepared to pay the piper.



Casey

 

[JyRO]

Sounds too expensive...

GAmes - I've not had access to the TDR for a couple weeks or so. I've been meaning to ask you something about what you posted:

If I pull my 5er at 60 mph I average almost 13 mpg. If I increase the speed to 63 it drops to less than 11 mpg. What that comes to in $$$ and time is that for every 300 miles I travel I gain 15 minutes and use 4 more gallons of fuel, roughly $22 an hour. Since I'm retired time is free but fuel is not. I'll stick with 60 mph.

I'm curious as to how you got $22 an hour? I did the math. I assumed you got 13 mpg @ 60 mph, and 10. 5 mpg @ 63 mph. Then I assumed the fuel cost to be $1. 60 per gallon. I actually came up with $2. 22 per hour (that way). My math said you would use ~1. 4 gallons more per hour at 63 mph. Multiplying that by $1. 60/gallon gave $2. 22 more per hour. And that seems to more closely jibe with what you said about using 4 more gallons in 300 miles. 4 more gallons would be ~$6. 40. 300 miles would take about 4. 75 hours @ 63 mph. That's about $1. 35 an hour.



Is it possible that you got a decimal off somewhere? Or are you counting something that I am not?



Understand that I'm not saying your wrong, I'm just trying to understand because $22/hour sounds mighty expensive to me for fuel cost.



- JyRO

 

[klenger]

JyRO: I think yiu are right. The TOTAL fuel cost per hour going 60 MPH at 10 MPG @ $1. 60 is only $9. 60.

 

[Dean Upson]

One thing that irks me, and I realize I'll get flamed for it, is when someone says something to the effect of, "I get X mpg no matter how I drive it. " What a crock (I think). I personally think that their vehicle must be driven similarly (erratically) from tank to tank.

I agree. I just got back from about 2000 miles of towing and averaged 10. 5 mpg. This is about what I got from my previous trucks and what I expected. The harder I pushed, the less mileage I got, stands to reason.



Dean

 

[RustyJC]

21,180 GCW (21,500 GCWR) towing a 12'4" tall (plus front A/C) 5ver with a target speed of 70 MPH in mixed flat/hilly towing with a stretch through Austin, TX stop-and-go traffic - 10. 5 MPG tops! Our V-10 3500 towing the same 5ver over the same route - 6. 5 MPG.



Rusty

 

[GAmes]

My math

JyRO



What I was figuring was to gain 15 minutes I would burn 4 extra gallons of fuel, so to gain an hour it would cost me 16 gallons of fuel, hence $22, or in the case of a 300 mile trip, 15 minutes cost $5. 50, a little less than your figure. What I am saying, I guess, is that in the long haul driving a little slower saves a lot of fuel.

 

[klenger]

I guess that makes sense.



Sometimes, going a bit slower can increase the milage enough to eliminate a fuel stop. Then it really pays.

 

[claymike]

I tow 21,500 gross and if there is no wind I will get high 11's. Went on a 5k trip last year towing and averaged 11. 2 mpg towing my 5er. Cant wait to see what this year brings

 

[DBF]

As an illustration of "flat plate drag", the only time I got less than 8mpg towing was a day going west in North Dakota and Montana driving straight into winds that must have been 30-40mph.



I couldn't even get the rig up to 60mph with the throttle on the floor.



I average 12. 3 towing my little 5er at 62-65.



DBF



(Edited 5/15 after looking back thru the milage spreadsheet. The day was 5/21/01 and ended in Miles City, MT. Geez, what a day. DBF)

 

[Headlight]

Nice too see! Honest reports on milage while towing. After reading numerous posts of fantistic miles per gallon, I thought I had a leak in my fuel tank. I guess not. Thanks for the honest reports.

 

[JyRO]

OK...

Hey GAmes - I see what you were saying now. It makes sense, I just wasn't thinking of it the way you were. Fighting drag makes all the difference and speed exponentially increases drag.



If I had 4. 10's, I'd be towing 60 - 65 mph. But with the 3. 54's, it doesn't make enough power to keep me happy (in 6th gear) until about 67 mph. But I'll take slightly less than 11 mpg while running 67 - 70 with a GCW or 16,540 lb. I can't complain about that.



- JyRO