Fuel Economy fuel economy - classic vs. aerodynamic trucks

[syd]

I drove freightliner against heavy winds even with pedal to the metal my speed dropped from 70miles (governed) to 45 miles an hour so these aero trucks are not so aero

 

[mndriver]

I drove freightliner against heavy winds even with pedal to the metal my speed dropped from 70miles (governed) to 45 miles an hour so these aero trucks are not so aero

Sounds more like a mechanical issue

 

[Duck]

Sounds more like a mechanical issue

He did say it was a Freightliner.

 

[ironpony]

Sounds more like a mechanical issue

He did say it was a Freightliner.

I think the key phrase is, "against a heavy wind."

The aero truck diminishes drag, it doesn't magically eliminate it.

 

[Duck]

I think the key phrase is, "against a heavy wind."

The aero truck diminishes drag, it doesn't magically eliminate it.

If a headwind can slow you down to 45, either something is wrong with the truck,... or you should be getting off the road & looking for a tornado shelter.

 

[ironpony]

Down-slope winds can reach 50 or 60 mph at times off the Rockies. These are straight line winds, generally west winds... so heading into them on I40 or I80 isn't particularly dangerous... in a heavy truck.

It may take ya a couple 'o days to get from Pine Bluff WY to Cheyenne though!

 

[Duck]

Down-slope winds can reach 50 or 60 mph at times off the Rockies. These are straight line winds, generally west winds... so heading into them on I40 or I80 isn't particularly dangerous... in a heavy truck.

It may take ya a couple 'o days to get from Pine Bluff WY to Cheyenne though!

And that, folks, is why you shouldn't drive trucks powered by Briggs & Stratton.

 

[ironpony]

And that, folks, is why you shouldn't drive trucks powered by Briggs & Stratton.

Thanks, I'll avoid anything that looks like a Trabant...

 

[Duck]

Thanks, I'll avoid anything that looks like a Trabant...

I had to Google that.

The 50 Worst Cars of All Time - TIME

LMAO. I think the Yugo I had when I was 14 had 54 hp.

My lawnmower has 23 hp.

That little car looks like fun though. I'd pull out its engine and put in a big bad V-twin Briggs Vanguard engine and hot rod it around.

@Skateboard's commie ass would be jealous.

 

[Mike]

I would really like to see a good study on these trucks in terms of aerodynamics and the true mpg advantage.

I know the common claim is 1 mpg, but I am not 100% sold on the accuracy of that.

Fact is, I want to buy a new truck soon, glider, and there is a battle inside my head between a t660 and a w900. Fuel economy is important, but so is a more comfortable ride.

 

[Duck]

I would really like to see a good study on these trucks in terms of aerodynamics and the true mpg advantage.

I know the common claim is 1 mpg, but I am not 100% sold on the accuracy of that.

Fact is, I want to buy a new truck soon, glider, and there is a battle inside my head between a t660 and a w900. Fuel economy is important, but so is a more comfortable ride.

T-660 has a comfortable ride & you'll barely notice crosswinds.
Neither of those trucks has the interior space your 680 has though.

 

[mndriver]

Wide body vs traditional......

I'd hate to give up the space

 

[Mike]

T-660 has a comfortable ride & you'll barely notice crosswinds.
Neither of those trucks has the interior space your 680 has though.

Interior space is not a big deal, as I am happy with a narrower cab. You can always gain space with a studio sleeper

My main concern is the true loss in MPG.

 

[mndriver]

Willing to pay $12-15,000 s year to look krwl?

 

[Mike]

Willing to pay $12-15,000 s year to look krwl?

Nope.

I can get a w900 cheaper than a t660, which is why I want to be more sure about the fuel mileage difference.

 

[mndriver]

Buddy is running a w9 with a3406E. He's consistently 1-1.5 mpg less than me. Or was. Now he's closer to 2 mpg less.

 

[Mike]

Buddy is running a w9 with a3406E. He's consistently 1-1.5 mpg less than me. Or was. Now he's closer to 2 mpg less.

I would expect that.

I'm looking at an identical engine/tranny/differential setup though.

You guys could probably swap drivetrain and the w9 would end up with better mpg numbers

 

[mndriver]

He's running 1425-1450 at about 67 mph too. Same as I am. We both run heavy over 70k gross regular.

He's running tall 24.5, I'm running lp22.5

He's running low 5's, I'm now low 7's.

He does run a 265" and a spread axle though.

 

[ironpony]

Its mostly all that junk hanging off the classic large cars that kills the aerodynamic efficiency. Loose all that chromed junk (which, of course, gives them the "look") and they get a lot more efficient at moving air out of the way.

 

[mndriver]

The Pete 386 and 587 are piquing my interest, but with the century finally performing like I expect it to, it's getting hard to justify anything new unless I see better than 9.5 mpg all the time.