Volvo Trucks North America checks off multiple customer requisites with its model year 2017 powertrain refinements—increased fuel efficiency, productivity, uptime, and more efficient chassis packaging. Major enhancements include turbo compounding for the North American Volvo D13 engine; the introduction of Volvo I-Shift automated manual transmission (AMT) with crawler gears; Volvo I-See predictive cruise control; and a one-box exhaust aftertreatment system (EATS).
As a result of the improvements to the D11 and D13 engines, Volvo claims to deliver between 2.2 to 6.5% better fuel efficiency (FE) with the 2017 engines compared with the previous generation. It’s “the most fuel-efficient [lineup] we’ve ever offered in North America,” said Göran Nyberg, President of Volvo Trucks North America.
The Volvo D13 with turbo compounding was designed for long-haul, steady-state applications. Turbo compounding is a technology that recovers wasted exhaust heat and converts it to useable mechanical energy in the form of 50 additional hp (37 kW) that is transferred back into the engine, resulting in a 6.5% FE improvement.
The D13 with turbo compounding can also be spec’d with Volvo’s XE (eXceptional Efficiency) powertrain packages or in super direct drive. Through downspeeding, XE allows the engine to cruise at up to 300 rpm less than the average truck sold today, according to Volvo. The D13 with turbo compounding is available on an XE driveline with a 2.47 rear axle ratio.
The truck maker notes that more than 27% of all Volvo models sold in 2015 featured an XE package.
Updates to Volvo’s 11-L D11 and standard 13-L D13 include a common-rail fuel system that contributes to FE improvements through finer control of the fuel injection. An updated EGR (exhaust gas recirculation) flow sensor has a new double-wall casing that reduces condensation and soot buildup in cold weather. A low-pressure fuel system features an improved aftertreatment dosing module that is integrated into the fuel filter housing for easier serviceability. Upgrades to the two-speed coolant pump for both engines also improve FE as a result of reduced parasitic losses. The new intake throttle enables a faster warm-up when the engine is started.
The updated D13 also features a new wave piston that increases the compression ratio. Improved flame propagation reduces soot and increases cylinder efficiency. Available in the Volvo VN, VHD and VAH models, the D13 offers a FE improvement of up to 2.5% compared to the previous D13. These engine enhancements are also included in the D13 with turbo compounding.
The 2017 Volvo D11 offers up to 425 hp (317 kW)—an increase of 20 hp (15 kW)—and 1550 lb·ft (2100 N·m) of torque, while also delivering up to a 2.2% FE improvement compared to its predecessor. The D11 is suitable for regional, less than truckload (LTL), and pickup-and-delivery applications. It’s also available in Volvo VN daycabs, VNM 430 and VNL 430 sleeper models, VAH and VHD models.
Volvo Trucks North America is preparing for production at the Hagerstown, MD, facility. The site, which assembles the full line of Volvo Trucks’ proprietary engines and I-Shift AMTs, will begin production of the updated 2017 powertrain in late 2016.
I-Shift with Crawler Gears; I-See predictive cruise
Designed with crawler functionality and startability, the I-Shift with Crawler Gears automated manual transmission is suitable for applications requiring a slow speed and maneuverability—such as concrete mixers with curb-pouring capability, asphalt paving, spreaders, dump trucks, heavy haul and line painters. The I-Shift with Crawler Gears also ensures startability for heavy haul and up to 220,000 lb GCW or more with application approval.
I-Shift with Crawler Gears will be available in two versions: 14 forward gears, including one low crawler gear (19.38 gear ratio) and one ultra-low crawler gear (32.04 gear ratio), which can operate down to 0.6 mph with 3.58 rear axle ratio; and 13 forward gears, including one low crawler gear (17.54 ratio) and an overall ratio of 22.35.
The overall ratio of the 14-speed version, 41.08 to 1, is more than double that of the I-Shift. Depending on application area, I-Shift is available with or without two reverse crawler gears, making it possible to reverse extremely slowly.
Available as an overdrive in Volvo VHD, VNX, VNM and VNL models, the I-Shift with Crawler Gears can be spec’d with Volvo D11, D13 and D16 engines.
All I-Shift models, spec’d in 83% of Volvo-powered vehicles in 2015, receive revised hardware for increased durability, including an upgraded countershaft for faster shifting and improved performance.
The transmission received additional updates to improve shift performance and overall durability, including improved split synchronizer components, an updated engaging sleeve, and main box parts made from reinforced material. The transmission’s software has also been optimized for shifting in high-weight applications.
New software enhancements, in the form of Volvo’s I-See predictive cruise control, can help improve fuel efficiency by learning and adapting to the road. The system stores up to 4500 different hills.
The built-in electronics constantly monitor factors such as road grade, speed, weight, and engine load to help maintain the most efficient gear possible. It optimizes gear shifting on hilly terrain by building speed before the hill, curbing speed before the crest, Eco-Rolling down the hill, and engine braking if necessary.
I-Shift is a key component to Volvo’s XE powertrain package. The inclusion of the new I-Shift with Crawler Gears in the XE Adaptive Gearing package expands the capabilities of XE from 80,000 lb up to 110,000 lb GCW as the low gear ratios maintain startability and enhance slow speed performance on softer ground.
One-box exhaust aftertreatment system
Volvo’s new one-box exhaust aftertreatment system (EATS) combines the diesel particulate filter (DPF) with the selective catalytic reduction (SCR) and diesel exhaust fluid doser into a single unit. The system also features a new copper-zeolite coating that improves low temperature NOx conversion for improved emissions.
The new design configuration results in better thermal performance for improved efficiency, smaller packaging requirements, and an approximately 17-lb (7.7-kg) weight reduction compared with the two-box unit. This provides additional frame rail space for packaging flexibility.
The new one-box EATS will be standard on the D11- and D13-equipped powertrains. The two-box solution will remain on the D16.