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Food for thought, why hasn't fuel economy improved more than it ha

Black02Silverado

By Black02Silverado
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Black02Silverado Senior Enthusiast

Black02Silverado

Posted
Posted

Food for thought but with today's technology one would thing we would be a lot farther along with fuel economy than we are. Case in point. My 2002 Silverado with a 5.3 4x4 extended cab gets on average 16mpg, If I want I can get 19 but that is keeping it at 55mph and taking it easy. Spring forward to todays new GM vehicles with direct injection and 8sp transmissions and they are only getting 20mpg. To me that isn't much of an advancement in economy. Come to think of it, my dad's 1977 Chevy 1500 stepside with a three on the tree and a 350ci engine got 15mpg. Funny, a three speed and a carborated engine getting what modern tech is getting today.

Another point was when I had my 91 VW Jetta diesel, I was getting 50mpg out of it as well as when I had my parents old 1979 Rabbit diesel it got 50mpg. Granted I know that emissions have a major play in what diesels get now but seems to me one would thing we would be getting the same mileage on an average mpg on new diesels more so than not. My Cruze diesel gets consistent 45mpg but I have been able to get 50mpg if I really hyper-mile.

Just seems odd that we are no farther along than we are when it comes to economy.

Irby1757 Enthusiast

Irby1757

Posted
Posted

At the end of the day, more fuel consumption equals more money for a lot of people. This can be said for the stall of releasing electric vehicles into the market as well. Telsa kind of blew that up for manufacturers and forced their hand.

 

Even though on this forum fuel consumption is discussed at length, many still choose to modify their vehicles and take away the advancements that have been made in that area. So it is not something that generally many cause a stir over. I would love to get 30 mpg with a 6" lift, but I also want to have the sound and performance of a V8. Until that time comes, I will continue driving as efficiently as I can with what I have, knowing that the next steps forward may be annoying to me (start-stop technology).

O_J_Simpson Senior Enthusiast

O_J_Simpson

Posted
Posted

Lets see. Just a few thoughts of the top of my head.

 

Fuel today sucks. Not near the same BTU value as the old stuff. Takes more fuel to go the same distance.

 

Cleaner emissions requires burning more fuel. Some of those dirty carburetor cars from the late 80's got 45-50 MPG.

 

Trucks are getting heavier. This trend is starting to be reversed. Expect others to follow Fords lead here of using lighter weight materials.

 

Speed limits are much higher. The double nickle has been replaced by 80-85 MPH speed limits on the highways.

 

The biggest factor that the manufactures know: No one buys a fuel size truck because it gets great mileage. If we can afford the new loaded out truck, you can afford the fuel.

barry G Senior Enthusiast

barry G

Posted
Posted

fuel mileage can exist, and it leads to more traffic.

the gov't has a lot of sheep guiding evil to do.

we get what we get because of it.

 

Necessity makes the ride.

a back crunching ten geared subaru from the 80s is at 30mpg in hot rod mode.

 

just can't do much with it.

 

my dads 2016 and my 1996 manual v8 is nearly identical fuel mileage.

they are both good for trucks. Go a little past 20mpg on the highways.

 

there is some darker ages than others with the trucks, forums like this can reveal them.

I am still defending what is and was good.

Chevymetal Enthusiast

Chevymetal

Posted
Posted

Today's trucks also make a hell of a lot more power than they used too. That takes fuel to do it. My 09 makes 315 hp and gets 15 mpg. My 88 K5 made 210 hp and got similar mileage. If they made a V8 today that only made 210 hp it would prob burn a lot less fuel. But that's not what the market demands. We want more power and as long as the gas mileage doesn't drop below where it's always been, we'll keep buying trucks.

MikeNH Senior Enthusiast

MikeNH

Posted
Posted

Cars and trucks are more powerful. Way more. They're heavier. Safety stuff, comfort and tech. They're bigger physically.

Donstar Senior Enthusiast

Donstar

Posted
Posted

Interesting discussion. I often wonder the same thing! Gas mileage has improved significantly. Instead of pocketing the savings, the market is cashing in the savings for more power. The discussions on the 6.2 as compared to those on the 4.3 illustrate the thoughts of many truck buyers. The 150 hp trucks of the 70's had ample power for a 1/2 ton but they were hard on gas consumption. There is so much more that can be done with transmissions and gearing, imo.

diyer2 Senior Enthusiast

diyer2

Posted
Posted

I think they have done a great job. More power, better ride, etc.

 

I'll buy the gas for these reasons.

 

It's a truck.

 

My truck will do all the things the wife's car will do, get groceries, go to moms, work etc.

 

Her car won't tow my boat, pull a U-Haul trailer, haul building material, etc. etc.

 

Not to mention I'm a truck guy, not A CAR guy.

 

:happysad:

KARNUT Senior Enthusiast

KARNUT

Posted
Posted

Every car and truck I've owned has improved dramatically in fuel mileage with new models. My 74 impala got 18 miles per gallon. My 94 got 23. My wife's 11 Genesis with more HP gets almost 30. My 70s Ford 460 got 8 miles per gallon. My 454s got a little better the 6.0 in a 3/4 ton gets high teens. Half ton have the same results. My 14 5.3 could get 24 miles per gallon on the highway. Same with 4 bangers. I have an Elantra that gets 24 miles per gallon in town, my 17 Camry gets 30 almost 40 on the highway with 50 more HP. I got 30 mpg with a 300HP Santa Fe on the highway. Big improvements across the board.

 

 

Sent from my iPhone using Tapatalk

Loco-diablo Senior Enthusiast

Loco-diablo

Posted
Posted

Lets see. Just a few thoughts of the top of my head.

 

Fuel today sucks. Not near the same BTU value as the old stuff. Takes more fuel to go the same distance.

 

Cleaner emissions requires burning more fuel. Some of those dirty carburetor cars from the late 80's got 45-50 MPG.

 

Trucks are getting heavier. This trend is starting to be reversed. Expect others to follow Fords lead here of using lighter weight materials.

 

Speed limits are much higher. The double nickle has been replaced by 80-85 MPH speed limits on the highways.

 

The biggest factor that the manufactures know: No one buys a fuel size truck because it gets great mileage. If we can afford the new loaded out truck, you can afford the fuel.

You're spot on. I'm averaging about 19.5 mpg with my 2017 5.3 DC.. I'm happy with this. It's pretty damn big when compared to my 2008 V6 Tacoma, yet it does about the same mpg.

For comparison, I have 2015, 5 cylinder Volvo turbo that get about 25 mpg on average. Much lighter than my truck.

Unless they lighten the weight, I can't see these gas powered trucks doing much better.

 

 

Sent from my iPhone using Tapatalk

Donstar Senior Enthusiast

Donstar

Posted
Posted

I don't think there is any dispute that fuel consumption rates have improved but I believe the op was referring to the speed of this change. I am confident that consumers drive the rate of change. GM currently produces a V6 for its 1/2 tons that is more powerful than most V8 pickups of previous decades and takes almost 50% less fuel. The V6 is not as popular as it should be because for a few dollars more, and small increase in gas consumption, consumers can buy a much more powerful V8. Manufacturers will produce what sells while maintaining legislated environmental requirements. If consumers clamored for a 1-2 mpg savings then you may see greater speed in the race to reduce fuel consumption!

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