Ultra-scientific aerodynamic mpg study.

[salesrep]

..on a whim hit the mpg reset on a two lane route into a 35 mph head wind at 10;30 this morning,,,17.7 mpg for the 25 mile stretch with 2 stop signs, cruise set at 64. Had to gun it twice around semis. 05 /buick rainier with 240,000 running that good schaeffer's oil.
Two hours later, exact same route, with a 35 mph tail wind, same two stop signs, no passing.........24.4.

Okay, not THAT scientific, but whoa what a difference.

 

[CT8]

2.7 ecoboost p/u fairly flat highway 140 mile trip cruise control at 70 mph a fairly consistent barely under 25 mpg. Same trip cruise control 65 a consistent 26 mpgs. Those are so far. I would consider that ideal conditions.

 

[OneEyeJack]

A co-worker is doing something similar with his brand new Ford pickup but with a different slant. He makes an early Sunday morning commute across the desert at 3:00AM at 75mph for 200 miles on the cruise control with no traffic and no stops but with a different goal. The object of this test is to decide to run with the tail gate up or down. You'd think that down would be better but so far it is consistently better with the tail gate up. It's worth almost 1 mile per gallon.

 

[tig1]

I had that recently on a trip to Rolla, Mo. from Granite City, Il. Driving into a 25MPH headwind I got 27MPG. Driving back home it jumped to 32MPG.

 

[Pop_Rivit]

Originally Posted By: OneEyeJack
You'd think that down would be better but so far it is consistently better with the tail gate up. It's worth almost 1 mile per gallon.


The myth of the tail gate down getting better fuel mileage was debunked years ago.

 

[Danno]

Originally Posted By: OneEyeJack
A co-worker is doing something similar with his brand new Ford pickup but with a different slant. He makes an early Sunday morning commute across the desert at 3:00AM at 75mph for 200 miles on the cruise control with no traffic and no stops but with a different goal. The object of this test is to decide to run with the tail gate up or down. You'd think that down would be better but so far it is consistently better with the tail gate up. It's worth almost 1 mile per gallon.

Yes, confirmed by Myth Busters. Tail gate up is better for fuel economy.

 

[Inspecktor]

Originally Posted By: OneEyeJack
A co-worker is doing something similar with his brand new Ford pickup but with a different slant. He makes an early Sunday morning commute across the desert at 3:00AM at 75mph for 200 miles on the cruise control with no traffic and no stops but with a different goal. The object of this test is to decide to run with the tail gate up or down. You'd think that down would be better but so far it is consistently better with the tail gate up. It's worth almost 1 mile per gallon.
Mythbusters did a series of tests that verified better mpg with tailgate up. They hypothesized it was due to more turbulence behind the cab with gate down, when up a vortex of air in the bed keeps airflow above the bed until past the rear of the truck.

 

[Kuato]

Originally Posted By: salesrep
..on a whim hit the mpg reset on a two lane route into a 35 mph head wind at 10;30 this morning,,,17.7 mpg for the 25 mile stretch with 2 stop signs, cruise set at 64. Had to gun it twice around semis. 05 /buick rainier with 240,000 running that good schaeffer's oil.
Two hours later, exact same route, with a 35 mph tail wind, same two stop signs, no passing.........24.4.

Okay, not THAT scientific, but whoa what a difference.


Plenty scientific to illustrate how much wind resistance counts for mpg. Even more for vehicles with a larger frontal area.`

 

[Gasbuggy]

Tailgate a coach bus and you'll be in MPG heaven. (perfect joke set up)

 

[HTSS_TR]

Originally Posted By: Kuato
Originally Posted By: salesrep
..on a whim hit the mpg reset on a two lane route into a 35 mph head wind at 10;30 this morning,,,17.7 mpg for the 25 mile stretch with 2 stop signs, cruise set at 64. Had to gun it twice around semis. 05 /buick rainier with 240,000 running that good schaeffer's oil.
Two hours later, exact same route, with a 35 mph tail wind, same two stop signs, no passing.........24.4.

Okay, not THAT scientific, but whoa what a difference.


Plenty scientific to illustrate how much wind resistance counts for mpg. Even more for vehicles with a larger frontal area.`

Exactly. Wind resistance is the real gas mileage killer. Reducing speed from 85 MPH to 65 MPH with no wind in any direction would increase gas mileage up to 20% or more.

 

[OneEyeJack]

Mythbusters also proved that tailgating a big truck really improved one's fuel mileage.

 

[HTSS_TR]

Trying to improve 1-2 MPG by tailgating 18 wheeler and get rocks on windshield and couple hundred buck to replace it ?

 

[OneEyeJack]

Mythbusters predicted much better results. Much better.

 

[supton]

Originally Posted By: HTSS_TR
Trying to improve 1-2 MPG by tailgating 18 wheeler and get rocks on windshield and couple hundred buck to replace it ?


Up here you don't have to tailgate to have that happen. Heck, after five years you'll want to have it replaced even if not cracked.

 

[Silverado12]

The sandblasted windshield LOL. I drive an 18 wheeler and after about 300K miles the windshield comes out due to the sandblasting, wiper marks, etc. cause a visibility issue.

 

[Kuato]

Originally Posted By: HTSS_TR
Trying to improve 1-2 MPG by tailgating 18 wheeler and get rocks on windshield and couple hundred buck to replace it ?


If you get close enough, all that debris will miss your windshield.

I don't know how I know that.