Todays trucks where is the MPG's

[Wolfy]

Schmism, one reason for that is heavy trucks have a much wider gear range than pickups. And most are still gear shift, unlike most new pickups. Also, the inline 6 is a fuel sipper by nature. I was watching Modern Marvels, and learned diesel/electric trains are like 7 times more efficient than heavy trucks. Maybe that technology needs to be incorporated into pickups.

 

[Turbys_1700]

My current ride is an 03 F350 4 door 4x4 dually with a 7.3...
Running an 80 HP program with 4" stainless exhaust and big air filter I average 14 to 15 mpg driving back and forth to work...
Pulling my 30' 5th wheel camper that weighs in @ 10K# I average 11 mpg...
As stated before, fuel mileage is directly related to horsepower, air resistance, and weight...
I don't drive my dually because it is an economy car...
I drive my dually because I like it...

 

[Highbeam]

heres what i dont get.

My 2001 E350 pulling 8k lbs (20' equipment trailer with tractor and additional stuff) gets 10mpg at 65 mph. It gets 12mpg with 3K behind it and 15 or so empty.

So my "empty" van that weights say 5K lbs pulling another 8K lbs ... lets ball park that at 15K lbs. GCVW... at 10mpg

now step up to the big boys.... Modern semi get 5-7 mpg at 80K lbs

so if you scale my 15k lbs over 10mpg up to 80k lbs it would be....(carry the 2) 1.8 mpg ?!?!

or look at it the other way.... if the semi gets 7mpg at 80K lbs then i why cant i get 37.3 mpg in my 15K truck?

something ant right in denmark when an 80K lb truck can get 2/3 the gas millage our little trucks get....

Ah, but it's not the weight. It is the aerodynamics. The frontal area that the semi is pushing is bigger that yours, say double. It's mpg is half. Okay. The weight is all in back and other than stopping or starting, it makes little difference in consumption. What you spend raising that weight when you go uphill, you get back when you go downhill.

Those big rigs do get great mpgs. Now consider a train. Those buggers get the best miles per gallon per ton. Both of these are optimized for fuel efficiency. Neither use a lame automatic transmission like your van.

on edit: bugger, there was a page two and wolfy made some of my points.

Also consider boats, much better mpg per ton. Slower speeds, less friction.

 

[schmism]

The weight is all in back and other than stopping or starting, it makes little difference in consumption.

See thats exactly the opposite feel as alot of other people that have already posted... that modern trucks weigh more than 30 yo trucks and they point to that as one of the reasons they get the same or worse mpg....

I do think lbs per hp are an issue.... when a semi has a 400hp engine and a pickup has a 400hp engine....

SO ya id love to see what would happen to small truck mpg if you scaled it off a big truck.... in HP, in gears, in weight etc. My gut feeling is its already been done but the US market doesnt get those options, Its only overseas in the third world market that get those (awesome) trucks.

 

[dodge man]

On the highway, weight is not that big of a factor, but around town, in stop and go driving, the weight is a huge penalty. Keep in mind semis, the long haulers even more so, are doing a lot of highway cruising.

 

[zzvyb6]

The difference in the semi and the pickup is in the torque available. The power levels to maintain speed do scale by weight. If your pickup took 1/2 mile to get up to speed, it wouldn't be considered safe or desireable. If the semi had enough torque to get up to 60 mph in 10 seconds or less, it would get 1/100 the mpg.

Your Silverado (like my Tahoe) has a system in it to run on 4 cylinders instead of 8 when driving at a constant speed. You can watch it switch back and forth by picking thru the vehicle information buttons on the dash. Most people can hear or feel the system switch, Then you can learn to modulate the throttle to keep it in 4 cyl mode as much as possible. Use of cruise control makes it waste gas by using power (fuel) to maintain a set speed. Then your truck can get well over 20 mpg WITH the trailer even. I can get 24 out on I-96 with 80 bales of hay on the snowmobile trailer.

 

[slowzuki]

Exactly weight hurts in stop and go and in hilly terrain. In hills, you end up braking going down (waste of energy), and still go too fast (wastes energy) then having to burn your fuel to make it back up the other side.

Also, less important but weight increases the rolling resistance of tires and bearings in the truck.

 

[Stubee]

To original question: 2010 Tundra DC 4X4 w. 4.6 = best 21.7 to 21.9 measured MPG on trips @ ~ 63 avg. mph calculated via hand, not vehicle computer. Fully loaded truck, no trailer. Mileage of course drops w. speed, temp, grade etc. Low as 14 mpg @ 80 mph in winter. Lowest towing mpg 17 mpg but only 2K trailer. Expect to be happy w. 10-11 mpg when I tow 6K or so.

 

[sandman2234]

I drive a tractor trailer for a living and I KNOW that weight makes a difference in the fuel mileage, even on flat ground (I live in Florida where we do have a little of that) Typical numbers would be about 2 mpg difference at 67 mph over empty.(5.2 mpg to almost 6.8 empty) It gets worse the faster you go, but can be a little better with a little slower. Get too slow and you end up in another gear, which will mess with the fuel mileage even worse.
David from jax

 

[clemsonfor]

Even with the emissions hardware on these trucks there's no way I'd want to go back to what we drove 30 years ago. My first diesel was a new '82 GMC with the 6.2 diesel. About 130 HP and maybe 250#/ft torque. It got twice the mileage my '79 F-350 w/460 gas engine got but by the time I had it three months it had blown two head gaskets. Traded it for a new '85 Ford F-350 with the 6.9 diesel. It got good mileage but was still low on power. Great engine, though.
If I stay around 60 mph I can get pretty decent mileage in my F-450's 6.4 diesel considering it weighs over 9,000#. These trucks have the aerodynamics of a brick so the faster you go the more fuel they'll suck down. I do like having 350 hp and 650 #/ft torque, pulls a trailer like it's not back there.

You cant compare that old deisel to a new one. That was an engineering nightmare for GM from what i have heard. It was a dog, needed to be turboed just to be decent. And this was basically the 350 made to run on deisel, not a true engineered diesel.