Commentary: Proper Tractor Specification – Impact on Efficiency and Driver Experience

June 03, 2015

Proper specification of a power unit can contribute to improved vehicle safety, better performance and improved efficiencies, less downtime, lower operational costs, and happier drivers.

The challenge is defining the term “proper.” With OEMs offering dozens of truck spec options, opportunities for error multiply. With vehicle uptime and safety at stake, how do you determine which components are “proper” for your application? And, how should your specifications be modified for a Natural Gas-powered unit?

Why not start from the ground up with the tire selection. Your choice in tires can significantly impact the fuel economy of your new trucks. Tire flex and road surface/tire friction serve to increase the build-up of heat in your truck’s tires, and heat is wasted energy. When selecting the tires for your new trucks, choose the least aggressive tread as possible (a straight groove tire will create the least friction). Consider low rolling resistance tires, which usually have a lower sidewall profile, reduce sidewall flexing and further reduce heat build-up.

Remember that the rolling resistance of a tire increases with the load range rating. Be sure to put enough tires on your truck to safely carry the load, but avoid over-rating your tires. If your next truck would normally come with dual tires on the rear axles, consider using wide-base “super-single” tires, which help reduce rolling resistance and total truck weight.

Another consideration is to optimize the Powertrain. Properly spec’ing your vehicle’s powertrain can have as much impact on fuel economy as any other item. An under-powered truck results in a shortened engine life, increased maintenance and higher fuel consumption. With engine capabilities today and the idea that more is better, many trucks on the road today are over-powered, resulting in an excessive capital cost and fuel consumption. The trick is to find the right balance between engine torque, horsepower and driveline gearing to ensure proper performance without having more engine than necessary. In many cases, trucks are over-powered simply because the rest of the powertrain is not properly designed.

A properly spec’d powertrain helps ensure that the truck’s engine operates within its peak efficiency power band. This means that except during initial launch, engine RPMs are never below the maximum torque point and never above the maximum horsepower point. The engine must have the necessary torque to launch the vehicle in a worst-case scenario and enough horsepower to achieve and maintain the desired road speed. With a Nat Gas power unit, the components of the unit’s specification become even more important. Due to changes in horsepower rating and torque, the power curve on a Nat Gas unit could vary significantly from a similar diesel power unit. Therefore different gear ratios and transmissions need to be considered to provide a comparable driving experience and truck efficiency.

Most truck dealers have a computer software program that will match engine ratings, transmission gear ratios and final drive (rear end) gear ratios to achieve the desired performance. Just make sure that your dealer knows your performance requirements. Some of the things you will need to provide the dealer include gross vehicle combination weight, road surface type that unit will operate, maximum desired road speed, highway vs. city operation, etc. By working with your OEM provider and/or engine manufacturer, you can optimize your powertrain for peak fuel efficiency. You may be surprised to discover that you achieve the desired vehicle performance without buying the largest engine available and putting the deepest reduction rear available in the truck. This means better fuel economy and probably a lower initial cost.

Natural Gas Vehicle News

Ryder Supplying CNG Trucks to Florida Dairy Fleet

Ryder System Inc. has signed a full-service lease agreement to supply three compressed natural gas (CNG) heavy-duty trucks to Florida-based dairy M&B Products.

Louisiana Clean Fuels Honors Republic with Fleet of the Year Award

Republic Services of Baton Rouge has been awarded the prestigious Fleet of the Year Award by Louisiana Clean Fuels. Republic introduced 42 CNG powered collection trucks and installed a new natural gas fueling station to support its expanding fleet in Baton Rouge in 2014. Republic plans to deploy 18 additional CNG powered trucks this summer.

Gibson County Utility District Opens CNG Station

As part of the Tennessee Gas Association's compressed natural gas (CNG) rally across the state last week, the Gibson County Utility District celebrated the grand opening of its public CNG fueling station in Trenton, Tenn.

Rebates for switching from gasoline to cleaner-burning fuels advance in Legislature

Legislative Bill 581 would provide $500,000 in rebates for converting vehicles to burn compressed natural gas, liquefied natural gas or higher percentages of ethanol.

What a gas: Waste industry's adoption of CNG outpaces others

Fans of CNG-fueled vehicles say they are cleaner-burning, quieter, a smoother ride for drivers and cheaper to operate. Using these vehicles is growing more popular in other industries, as well as in waste and recycling, and the main factor is that natural gas is cheaper than diesel fuel right now. But industry pros say the use of these vehicles is here to stay, regardless of oil or natural gas prices.

Construction Begins on CNG Trucking Terminal

“You may have heard a term called mobile pipeline, virtual pipeline, pipeline on wheels. This is what we are doing. We are taking Pennsylvania gas and we are taking it to folks here in Pennsylvania,” said Compass Natural Gas executive vice president Yves Pollart.

Delaware Express Converts Vans to Compressed Natural Gas

Delaware Express (DES), which offers airport shuttle services, motor coach and car services in Delaware and surrounding states, recently converted multiple vans to compressed natural gas (CNG). With the help of a partial government clean energy grant, DES says it retrofitted the vehicles to lessen the company's environmental impact.

Fully Converted Fleet Operator Marks Retirement of Its First CNG Buses

The Centre Area Transportation Authority (CATA), which years ago made a full fleet conversion to compressed natural gas (CNG), will officially retire the last of its first-generation CNG buses this Friday.

Fuel Price News

US Shale Will Not Bounce Back At Current Prices

Deutsche Bank’s research continues to support $70 as the price whereby production can be added as supported by cash flow. They believe at $72 operation cash flow will only equal capital spending for oil producers in 2016/2017.

Natural gas reality check, Part 1: Diesel’s dip and navigating today’s challenges

Lower diesel costs, coupled with strides made by OEMs and engine makers to improve the fuel economy of traditional diesel-powered trucks and engines, have combined to stymie the natural gas market. Demand for natural gas equipment is not growing, nor is it dropping. Given the inherent volatility in diesel prices, it is unlikely the low-cost fuel will remain at current levels for a long period of time.

Texas Now Produces More Natural Gas Than All Of OPEC

Everything is bigger in Texas, especially natural gas production. The Lone Star State alone produces more natural gas than every country in the world, except Russia, and that includes every member state of OPEC.

Oil leaps 5 percent as dollar rally stalls, U.S. rigs fall

Crude oil prices jumped almost 5 percent on Friday, their biggest rally in 1-1/2 months, as a steady U.S. dollar and a bigger than expected drop in U.S. oil rigs in operation set off a renewed rush of bullish bets.

Crude jumps back above $60 level

A slowdown in domestic drilling sparked a rally on the crude markets Friday, adding some vigor to what had otherwise been a slow week for oil.

Oil to stabilize amid production worries

Crude oil prices may start to stabilize despite the prospect of increasing production, an industry watcher said Tuesday. U.S. drillers cut just one rig last week, bringing the number of rigs operating in U.S. oilfields to 659, compared with 1,528 a year ago

About Mansfield Energy Corp:

For 60 years, Mansfield has been creatively solving commercial, industrial, and municipal customers’ most demanding energy procurement, supply, and logistics challenges. Today, the company provides energy commodities and related services to 5,000 customers in 18,000 locations across the U.S. and Canada. The company’s expertise covers a broad range of transportation and facilities energy from traditional petroleum products, CNG, renewable fuels, and specialty chemicals to power and natural gas. Mansfield employees are committed to their customers’ success, abiding by five core principles - Integrity, Excellence, Conscientiousness, Innovation, and Personal Service. The company is headquartered in Gainesville, GA (just north of Atlanta) with regional operations centers located in Chicago, Dallas, Denver, Houston, Los Angeles, Minneapolis, Bloomington, MN, and Calgary, Alberta Canada.

For more information about Mansfield, call 800-695-6626, or visit our website at

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