Isuzu beginning production of N-Series diesels
8 hours ago
by Bruce W. Smith / Photos by Larry Walton & Ford
Few businesses know what their customers are going to want a year from now, or what the economy will be like when their new product rolls out five years in the future.
Such is the predicament automotive manufacturers face when planning for their next generation pickups: Their crystal ball has to be well-polished.
We’re pleased to report that a recent test drive of the 2011 Super Duty F-350 Crew Cab 4×4 turbo-diesel, and other iterations of the Super Duty line-up, showed Ford’s crystal ball working perfectly.
The new F-Series Super Duty looks nearly identical to the 2010 version save for a clam-shell hood and Ford Blue Ovals the size of footballs. But under the skin it’s a more capable truck on multiple levels.
Ride quality is also greatly improved as are interior noise levels. The single-rear-wheel models have far less rear-end jitter over rough road surfaces than the previous models, thanks to changes in both rear springs and shock re-design and tuning.
Ford spent a lot of time talking to its loyal, hard-working customers who depend on their Super Duties to perform day in and day out in the most demanding environments. Then they took those insights and focused on making changes from the inside out instead of outside in. The result is a package full of innovations to help heavy-duty pickup owners make better use of their time on the job.
ToolLink is a clever way to quickly inventory all the tools in your truck without doing anything more than turning on the ignition key. Ford’s mobile office management system can also connect directly to your office computer to bring your entire network into the Super Duty cab.
But the biggest news is under the hood. Nothing speaks efficiency to a Super Duty buyer like power, and the Blue Oval designed-and-built, 390hp, turbocharged 6.7L PowerStroke is Ford’s best truck diesel yet.
During my introduction to the new pickups in Arizona, I got a feel for its power and fuel economy while driving more than 200 miles over all sorts of roads and towing different trailers. Adam Gryglak, Ford’s lead diesel engineering manager, rode shotgun in an F-350 Crew Cab 4×4 diesel while I was behind the wheel.
“Five years ago,” says Gryglak, “our team started this new engine design with a clean sheet of paper, literally with a single-cylinder diesel on a bench, and worked our way out from there.”
This fresh start resulted in some noticeably different engine design features, which produced the results the Ford team wanted in power, quietness, durability and low emissions. (Ford’s previous diesel was built by Navistar/International.)
Diesel fuel economy hasn’t been discussed much by the pickup makers over the years. Now it’s a marketing point – and one of the many items displayed on the dash digital read-out.
We observed 21.6 mpg at the end of one 70-mile driving segment on open highway while hauling 1,000 pounds in the F-350 XLT’s bed. Impressive for a pickup packing a curb weight in excess of 7,000 pounds.
What’s even more impressive about the new 6.7L is its inboard exhaust and outboard intake architecture.
The cylinder heads are turned so the exhaust exits down the middle of the “V” between the heads and out the back of the engine, while the fuel rails and injectors sit on the outside of the heads. (For more engine details go to our website, www.propickupmag.com )
This new design increases exhaust flow, which leads to better throttle response and minimizes heat transfer to the engine compartment, which plays a big role in cooling under heavy loads.
The inside-out design also led to new thinking in the fuel-delivery process. This PowerStroke uses an air-to-water intercooler and a common-rail injection system with 30,000 psi behind the fuel delivered to the eight-hole piezo injectors firing as many as five times during each power cycle.
“When the main injection occurs, we improve fuel efficiency and reduce engine-induced noise and vibration because we have a slower ignition process,” explains Gryglak.
“When the fuel burns, it doesn’t burn with a traditional pop or bang. It’s one long, continuous power burn.”
Fuel efficiency is also helped by slimming down the new diesel with a compacted graphite iron (CGI) engine block, which is both stronger and lighter than cast iron. (Ford has been using CGI in engine blocks in other products around the world for several years.)
Another power-to-weight advantage the PowerStroke has is the DualBoost turbocharger design.
This tiny turbo behaves like a much larger twin-turbocharger, combining the quick response of a small turbocharger and the power-building volume of a large turbocharger in one unit. It, too, is tucked away between the heads.
I saw the advantages of the new turbo when towing trailers up steep grades, exploring a huge quarry near Wickenburg, Arizona, and in stop-and-go Phoenix city traffic. There was never the slightest hint of turbo-lag or lack of instant power.
There wasn’t a whiff of diesel in the air, either. The new engine is very clean. That’s because the exhaust is subjected to an array of technologies to comply with the 2010 federal emissions standards including the reduction of oxides of nitrogen (NOx).
The 2011 Super Duty exhaust aftertreatment system begins when the engine management computer mixes in a tiny amount of Diesel Exhaust Fluid (a special water/urea mixture) with the exhaust.
The DEF splits into ammonia and carbon dioxide in a catalytic device to produce inert nitrogen and water. Soot is then captured by the diesel particulate filter (DPF) that makes up the foreword section of a massive aftertreatment exhaust assembly under the cab.
The DPF assembly, which resembles a miniature multistage rocket more than a traditional catalytic converter, occasionally gets an extra dose of raw diesel—the fifth injection stage—when the sensors indicate soot is plugging up the DPF.
The extra fuel burns off the soot and all is good again. The dash display shows a little symbol when the burn-off is in process. The burn-off automatically ceases if the truck stops.
Speaking of stopping, let the DEF tank run dry and “you’re not going anywhere,” says Gryglak. The DEF is stored in a 5.5-gallon tank located behind the main fuel tank and it has its own filler. Gryglak says there’s enough fluid in the tank to last about 7,500 miles. The system starts warning of low fluid level around 800 miles before the tank needs refilling. DEF fluid is already available at most truck stops and will eventually be sold at most gas stations that carry diesel.
Ford Super Duty’s new diesel is backed up by a new six-speed automatic – the 6R140 heavy-duty TorqShift. It’s every bit as impressive as the engine and plays a big role in the fuel-economy gains. It’s also being used from one end of the Super Duty spectrum to the other, F250 to F-550, gas or diesel.
The new tranny, which has a deep low-gear and two overdrives, is lighter and a lot stronger than the one it replaces, bringing with it better off-the-line performance, lower rpm lockups, less heat generation and greatly extended service intervals.
Such improvements come from the use of a Lepelletier-style powerflow where the six speeds require only five clutches, and the speeds of the clutches relative to one another are low, increasing the efficiency and life expectancy of the transmission.
“With this architecture, the transmission can handle the enormous low-end torque produced by the new diesel engine as well as the high speeds produced by the new gas engine,” said Al Bruck, 6R140 transmission engineering manager.
The new transmission allows the diesel to lug down to 900rpm, while still locked, up for better fuel economy.
What I loved about the new transmission are the multiple shifting options: You can let it do all the thinking in Drive; you can use the toggle switch on the shift lever to go into the Progressive Range Select option; or you can shift into “M” and do all the shifts manually. In a nutshell, you have the ability to pick whatever gear or shift mode you like for the task at hand.
Regardless of mode, the shifts are fast and smooth. In fact, when the F-350 4×4 is empty the 6R140 snicks through the gears and into Sixth before the truck reaches 40mph.
Of course the 2011 Super Duty has an advanced “tow/haul” mode, which both lengthens and firms shifts on acceleration while employing an array of sophisticated electronic sensors to better predict the driver’s need for a downshift and provide engine braking and enhanced control.
Another nice feature is the Live Drive power take off output, which delivers power to aftermarket PTO attachments any time the engine is running.
The PTO is driven from a gear linked through the torque converter to the engine crankshaft so the transmission can power auxiliary equipment such as snowplows, aerial lifts, tow truck lifts, slide-backs, cement mixers, sprayers, dump beds or other equipment via drive shaft or hydraulic pump the moment the engine fires.
I’m always impressed by the capability of diesel Super Duties when the paved road ends and the work in dirt, rock, and sand begin. Tons of low-end torque and a strong four-wheel-drive system are great companions off-pavement, towing, hauling or playing.
Add in the new Ford E-locker option to the rear differential of the 2011 Super Duty and you now have superb off-pavement performer.
Traction control is further enhanced by a new hill-start assist feature that applies the brakes for a couple seconds after you take your foot off the brake to prevent rollback. The hill-descent control keeps the truck inching along without any of the ABS noise and grinding
experienced with similar systems.
The F-350 Super Duty Crew Cab 4×4 diesel shines brightest as a tow vehicle, which is how most of our readers will be using it.
Ford teamed up with Reese to offer factory-installed substructures for both fifth wheel ($450 option) and gooseneck applications, with the fifth wheel hitch assemblies and hidden gooseneck pins available at the Ford dealer.
Conventional towing on the factory-supplied F-350 receiver-hitch is limited to 8,000 pounds, and maxes out at 14,000 pounds when using a weight-distributing hitch. (See “Towing The Line,” p. 54)
Ford continues to offer its integrated trailer brake controller, power-folding and power-telescoping mirrors, while adding a sophisticated trailer sway control system as standard on all single-rear-wheel configurations.
In fact if there’s one single word to best describe the new Super Duties in general it’s “control.” Ford engineers and designers have done a remarkable job letting the driver have all the control needed when the task at hand requires it, while providing an array of automatic functions to take control of the situation when the driver just wants to drive.