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Heavy-Duty GM Pickup Fuel Economy Numbers Published By CR

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Gorehamj Senior Enthusiast

Gorehamj

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John Goreham
Contributing Writer, GM-Trucks.com
9-20-2017

Unlike light-duty trucks and every car sold in America, heavy-duty truck fuel economy data is hard to find. Consumer Reports knows this, and they recently tested heavy-duty pickups to determine the fuel economy. The interesting conclusion from Consumer Reports is that "What we found in our tests was that the efficiency of the diesel engines wasn't enough to offset the added bulk of these monstrous trucks. The heavy-duty diesels achieved only 14-15 mpg, which was 1-2 mpg less than their gasoline-powered light-duty counterparts."

 

Consumer Reports does not conform to the EPA test cycles. This makes sense, since the EPA never actually drives cars to get the numbers it publishes (and which we find to be spot-on in actual testing). Rather, they use a combination of dynamometer testing and an algorithm to determine fuel economy of a wide range of situations. Here's how Consumer Reports does its fuel economy testing: "We perform our own fuel-economy tests, independent of the government's often-quoted EPA figures and the manufacturers' claims. Using a precise fuel-flow measuring device spliced into the fuel line, we run two separate circuits. One is on a public highway at a steady 65 mph. That course is run in both directions to counteract any terrain and wind effects. A second is a simulated urban/suburban-driving test done at our track. It consists of predetermined acceleration, and deceleration rates, as well as idle time. Consumer Reports' overall fuel-economy numbers are derived from those fuel consumption tests."

 

You can view the Ram and Ford results at the link we have provided above. However, we thought it fair to publish the Chevy numbers for our membership. In CR's testing, the group found that the 2500 HD four-door crew-cab, with the 6.6-liter turbodiesel engine, four-wheel drive, and six-speed auto achieved a 14 MPG overall rating. CR found the Silverado 1500 with the 5.3-liter V8 earned a 16 MPG rating by comparison.

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sdeeter19555 Senior Enthusiast

sdeeter19555

Posted
Posted

 

attachicon.gifsilverado 2500 HD 17.jpg

John Goreham

Contributing Writer, GM-Trucks.com

9-20-2017

Unlike light-duty trucks and every car sold in America, heavy-duty truck fuel economy data is hard to find. Consumer Reports knows this, and they recently tested heavy-duty pickups to determine the fuel economy. The interesting conclusion from Consumer Reports is that "What we found in our tests was that the efficiency of the diesel engines wasn't enough to offset the added bulk of these monstrous trucks. The heavy-duty diesels achieved only 14-15 mpg, which was 1-2 mpg less than their gasoline-powered light-duty counterparts."

 

Consumer Reports does not conform to the EPA test cycles. This makes sense, since the EPA never actually drives cars to get the numbers it publishes (and which we find to be spot-on in actual testing). Rather, they use a combination of dynamometer testing and an algorithm to determine fuel economy of a wide range of situations. Here's how Consumer Reports does its fuel economy testing: "We perform our own fuel-economy tests, independent of the government's often-quoted EPA figures and the manufacturers' claims. Using a precise fuel-flow measuring device spliced into the fuel line, we run two separate circuits. One is on a public highway at a steady 65 mph. That course is run in both directions to counteract any terrain and wind effects. A second is a simulated urban/suburban-driving test done at our track. It consists of predetermined acceleration, and deceleration rates, as well as idle time. Consumer Reports' overall fuel-economy numbers are derived from those fuel consumption tests."

 

You can view the Ram and Ford results at the link we have provided above. However, we thought it fair to publish the Chevy numbers for our membership. In CR's testing, the group found that the 2500 HD four-door crew-cab, with the 6.6-liter turbodiesel engine, four-wheel drive, and six-speed auto achieved a 14 MPG overall rating. CR found the Silverado 1500 with the 5.3-liter V8 earned a 16 MPG rating by comparison.

Wow, not apples to apples?

 

Why compare a light-duty consumer-grade truck to a light-duty commercial-grade truck.

 

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5.3Avalanche Enthusiast

5.3Avalanche

Posted
Posted

What a stupid article. Why in the world would you compare a heavy duty 3/4 ton diesel's mileage to that of a half ton gasser's mileage? The trucks have completely different weights and capabilities and are not the primary reasons for buying each one. It would be more meaningful to provide towing mileage with the diesel and compare that to towing mileage with the 3/4 ton gassers. It's tests like these that really lower the credibility of consumer reports to me.

sdeeter19555 Senior Enthusiast

sdeeter19555

Posted
Posted

Think we are missing the point. You have SOME INFORMATION you never had before. Get happy.

But the information is useless to the consumer (think contractor) trying to decide between 2500 gas or 2500 diesel...they aren't going to be choosing between a 1500 and a 2500.

 

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5.3Avalanche Enthusiast

5.3Avalanche

Posted
Posted

Think we are missing the point. You have SOME INFORMATION you never had before. Get happy.

No, we get it. The point is that the data is not presented in a meaningful way to allow the CONSUMER to make a meaningful purchasing decision. Why they chose to highlight a heavy duty's mileage compared to a half ton. Why not also compare the mileage of the 3/4 tons to midsize cars too because that's SOME INFORMATION as well.

Colossus Senior Enthusiast

Colossus

Posted
Posted

Prior to 2008 and the DPF and eventually the DEF emissions crap, the Diesels got some respectable numbers for fuel economy.

Nanotech Environmental Enthusiast

Nanotech Environmental

Posted
Posted

The mileage numbers they are reporting are a lot lower than what almost everyone with these trucks are getting. How did they bungle it that badly?

 

Most people are averaging a lot closer to 20 mpg overall with the 5.3 1500's.

Same with the diesel 2500's. Most people are getting much higher overall numbers than what CR is reporting.

I have a 9000 mile overall average of over 20 mpg US on my '17 Sierra 1500 4x4 with 5.3 and 3.42 gearing. That includes highway, city, stop and go & everything.

Even when I tow an enclosed cargo trailer with 2000# of cargo, I get much better mileage than CR is reporting.

 

I've never put a lot of credence into CR's reporting & this just supports my position even more.

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted

Forget the comparison. You have some useful numbers for the 2500 that neither GM or the EPA are willing to or are mandated to report. And I might add at speeds closer to what you guys drive than the EPA simulator cycle. Clue, yes the 5.3 gas numbers are lower. The test is at higher speed.

 

When you say it isn't useful you mean to you. It's all it can mean unless you speak for all.

 

Read it all. Pick the fruit and leave the dirt on the roots.

5.3Avalanche Enthusiast

5.3Avalanche

Posted
Posted

Forget the comparison. You have some useful numbers for the 2500 that neither GM or the EPA are willing to or are mandated to report. And I might add at speeds closer to what you guys drive than the EPA simulator cycle. Clue, yes the 5.3 gas numbers are lower. The test is at higher speed.

 

When you say it isn't useful you mean to you. It's all it can mean unless you speak for all.

 

Read it all. Pick the fruit and leave the dirt on the roots.

 

This is what you're failing to understand, and your bold rhetoric does not help to support your point. The data they have provided is meaningless because it has been collected under a different set of constraints compared to the EPA or GM testing. The article also doesn't help the buyer understand whether it's worth spending the extra $10k to get a diesel in their 3/4 ton truck versus the gasser. Instead, they compare to a half ton truck which weighs differently, and has a completely different skillset.

 

Why should it be the reader's job to filter the information to find the tidbits that are relevant to them? If CR actually had a plan with this article, they should have filtered the fruit from the dirt before releasing the article. What they should have done is compared all heavy duty trucks, with both the diesel and gas equivalents. This would help someone choose between the two offerings within that same truck platform. Now that would have been a fantastic article with some substance as the comparison now has encompassing context. Is it nice that they did some fuel mileage testing? Sure it is!, but the way that it was presented is poor to say the least. The problem with their test is that it's not standardized, so you can't just take their values and compare them to EPA or other mandated testing. Another good aspect to add would have been some sort of towing test where they use the same equipment with a trailer with a mass that is a defined percentage of the maximum towing capacity.

 

This article does not really help the consumer make a purchasing decision, which is the intent of the CR mission.

Nanotech Environmental Enthusiast

Nanotech Environmental

Posted
Posted

Forget the comparison. You have some useful numbers for the 2500 that neither GM or the EPA are willing to or are mandated to report. And I might add at speeds closer to what you guys drive than the EPA simulator cycle. Clue, yes the 5.3 gas numbers are lower. The test is at higher speed.

 

When you say it isn't useful you mean to you. It's all it can mean unless you speak for all.

 

Read it all. Pick the fruit and leave the dirt on the roots.

I'd suggest the info isn't all that useful, as it's completely inaccurate. Nobody is getting real world mileage numbers that low in their 1500's with 5.3. Same with the diesel 2500's

barry G Senior Enthusiast

barry G

Posted
Posted

 

it is just showing the heavier truck is heavier at all times.

 

I think there is a k2500 spree with people who do not use them.

enthusiast mentality.

 

I am one keeping k1500 on my doors as I go into steel density unknown with custom building.

it will simply use more and more fuel as making it bigger does.

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted

I understand you two believe your opinions should be as important to everyone else as they are to you. I find information such as this very useful. That's another opinion. Opinions are not facts nor the truth. Here's some facts...

 

5.3 Motor data from Fuelly.com

 

http://www.fuelly.com/car/chevrolet/silverado_1500/2017?engineconfig_id=63&bodytype_id=&submodel_id=

 

Based on data from 67 vehicles, 1,444 fuel-ups and 439,317 miles of driving, the 2017 Chevrolet Silverado 1500 gets a combined Avg MPG of 16.46 with a 0.14 MPG margin of error.

 

​Enough said.

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