Study: roof racks waste 100 million gallons of gasoline a year in the U.S.

[Noahfreak]

Originally Posted by bentring

To be a bit more scientific with data and such, here is a starting point if you enjoy math.

Are they serious with that 26.1 mpg number for light trucks? Having driven several pickups, 2 of which had 4 bangers in them, I'd be hard pressed to believe that any model pickup would AVERAGE 26.1 mpg. Best I ever saw was 28 with my 2wd manual 4 cyl Frontier on a long flat highway drive at 55 mph. That truck averaged about 21 or 22 around town and could dip down into the teens at times. If they're including crossovers, even my wife's Escape crossover SUV with the 1.6L and FWD averages in the LOW 20's and she drives it like a grandma. Something is off with those numbers. The 18.5 number from 1980 is equally as ridiculous. I know that trucks can get better mileage than these EPA numbers, but like I said, in stock form those numbers are at the peak of capabilities in ideal conditions (flat ground, low speed limit, no stops) in my experience. The most fuel efficient cars I've driven are almost double the mpg of the most fuel efficient trucks I've driven.

[carolina guy]

Originally Posted by Noahfreak

Are they serious with that 26.1 mpg number for light trucks? Having driven several pickups, 2 of which had 4 bangers in them, I'd be hard pressed to believe that any model pickup would AVERAGE 26.1 mpg. Best I ever saw was 28 with my 2wd manual 4 cyl Frontier on a long flat highway drive at 55 mph. That truck averaged about 21 or 22 around town and could dip down into the teens at times. If they're including crossovers, even my wife's Escape crossover SUV with the 1.6L and FWD averages in the LOW 20's and she drives it like a grandma. Something is off with those numbers. The 18.5 number from 1980 is equally as ridiculous. I know that trucks can get better mileage than these EPA numbers, but like I said, in stock form those numbers are at the peak of capabilities in ideal conditions (flat ground, low speed limit, no stops) in my experience. The most fuel efficient cars I've driven are almost double the mpg of the most fuel efficient trucks I've driven.

I am getting VERY regular 21.5 mpg highway (at 75mph) for my 2004 f150 without much being done to it yet other than a efan...will be covering the bed soon and see if that helps.

[Frank Lee]

Originally Posted by carolina guy

I am getting VERY regular 21.5 mpg highway (at 75mph) for my 2004 f150 without much being done to it yet other than a efan...will be covering the bed soon and see if that helps.

Several times in the past I dug through the Ecomodder garage to see if there were any full size pickups averaging over 20 mpg. There were ZERO gassers and a very few diesels.

So I call B.S., your F150 is NOT getting over 20 ESPECIALLY at 75 mph.

[bentring]

Originally Posted by Noahfreak

Are they serious .

Personally I think they are either crazy or those are from the manufacturer, so either way the end result is the same.

Originally Posted by carolina guy

I am getting VERY regular 21.5 mpg highway (at 75mph) for my 2004 f150 without much being done to it yet other than a efan...will be covering the bed soon and see if that helps.

Coming home from work and talking about mpg, my father was getting an instant read out of 25ish mpg at 65 mph from his 2012/13? F150 v6. This trip was a couple of months ago and I haven't ridden with him since then until Friday. While we were going down the road I looked over at his readout and it was showing 14.2 for the tank. I mentioned that to him and he looked at me, grinned while he shrugged his shoulders and said "I really like to hear the twin turbos".

P.S. Me too Frank Lee. I just wasn't going to say it.

[carolina guy]

Originally Posted by bentring

Personally I think they are either crazy or those are from the manufacturer, so either way the end result is the same.



Coming home from work and talking about mpg, my father was getting an instant read out of 25ish mpg at 65 mph from his 2012/13? F150 v6. This trip was a couple of months ago and I haven't ridden with him since then until Friday. While we were going down the road I looked over at his readout and it was showing 14.2 for the tank. I mentioned that to him and he looked at me, grinned while he shrugged his shoulders and said "I really like to hear the twin turbos".

P.S. Me too Frank Lee. I just wasn't going to say it.

(*shrug*). I base the mpg claim from a daily 45 mile each way commute around Charlotte on 485 using my SG2 to get the average, not the instant. I don't have a factory trip computer in this car...just using the gold standards of fuel ups and the scan gauge to base it on
BTW...tried a full grille block, saw no improvement in mpg. If I run with a/c, mpg dropps by 1 mpg on average and driving 65 mph yields appx the same +/- .5 mpg the could be traffic or wind or a heavy/light foot, although about 1/2 of the trip is with cruise control. I run NC hwy 49 to I485 to I77 and then about 1/2 mile of side streets for the commute. 11 traffic lights each way.

So...I believe that I know what I am averaging on the highway...will update my fuel log tomorrow with several months that will include the average with the city portion that takes it down to 18 mpg city/hwy.

So, I will call bs on his bs. ;-). If I get the chance I will fill up at the start of the commute and end each day for a few days to eliminate grocery and lunch runs that drop the average.

[Frank Lee]

A gas log with actual entries is good to have if one is making mpg claims.

P.S. Don't do any stupid short fills either.

[carolina guy]

Originally Posted by Frank Lee

A gas log with actual entries is good to have if one is making mpg claims.

P.S. Don't do any stupid short fills either.

Agreed...was reading just before putting the kids to sleep and haven't updated in a while. Although before one calls BS one "should" have all the information, eh? :-). Short fills are accurate to get the highway portion that I was mentioning...the city only usually yields around 15 mpg in my experience around Charlotte either light or heavy footed.

My gas log on my phone shows 17.2 mpg city / highway over the last six months / 5500 miles tracked. That includes a lot of non commute local driving and getting mulch, lumber, rock, etc while hauling the wife and 4 kids instead of just myself on the highway with cruise control.

BTW: this is without turbos...just the old Vin W 4.6 auto with 233k on the clock.

[oldtamiyaphile]

Originally Posted by Noahfreak

The study didn't take into account the foregone larger vehicle that would be necessary to replace the roof rack. 25% off of a typical car's mpg is still better than most trucks and large SUVs, isn't it?

That's the point I was about to make

I used to drive a 'mid sized' VW Transporter, I didn't use the rook rack often so I removed it when not needed (also it didn't fit in car parks with the rack on).

I now have a 'small' Renault, but I need the roof rack too often to bother taking it off. It also provides a great place to mount a solar panel.

Best ever tank was with the roof rack and solar panel fitted.

The gain by downsizing the vehicle was about 40% factoring in the difference between diesel and petrol.

I don't think there's anywhere near a 25% hit for a standard roof rack (heck even my ~1200lb enclosed trailer only costs about that much - and that's city, it's less on the highway), for a 4x4 style roof cage maybe. I'd guess my Thule Wingbar costs 5% on the highway, so assuming you drive 50/50 city/highway the actual hit would be more like 3%.

[oil pan 4]

The biggest aero hit I remember seeing was when someone on here had a suburban like mine and removed a big ugly home made roof rack and picked up something like 1.5mpg which turned out to be slightly less than a 10% improvement. Which was not bad.

[carolina guy]

Originally Posted by oil pan 4

The biggest aero hit I remember seeing was when someone on here had a suburban like mine and removed a big ugly home made roof rack and picked up something like 1.5mpg which turned out to be slightly less than a 10% improvement. Which was not bad.

Our 2006 Grand Caravan has the roof rack with removable crossbars and the only difference I ever saw w/o them was about 1mpg when running empty on my commute (27mpg vs 26mpg)....and that was likely wishful as that is within the usual variance. When we get the car running again, I will do an a-b-a type test, but mostly for a grille block. ;-)