Workhorse chassisThe Workhorse W-20D/W-22D front-engine diesel chassis with its International MaxxForce 7 engine has taken a big leap in improving motorhome fuel economy, while providing outstanding torque for Class A motorhomes along with the quietest V8 diesel engine you might ever drive, according to a news release.

Independent tests at Bosch Proving Grounds in South Bend, Ind., had this chassis-engine match-up achieving up to 13.2 mpg, an almost unheard of figure for a Class A motorhome. The tests were conducted with a 32-foot Four Winds Serrano coach body and loaded to the maximum 20,500-pound GVWR. The Serrano has been drawing heavy consumer interest throughout 2009 and was named a “Best of Show” at the September Pennsylvania RV and Camping Show by RVbuddiesonline.com. The W20D chassis and MaxxForce 7 engine are both on display at the National RV Trade Show in Louisville this week along with the Serrano.

The latest version of the MaxxForce 7, V8 tuned for motorhomes generates 230 hp and 620 pound-feet of torque. “This high volume, rugged mid-range diesel engine is the heart of many International medium duty trucks. Now it is making its mark in the RV industry,” said Tony Monda, Workhorse Custom Chassis Corp. vice president of marketing. “Coupled with the six-speed Allison transmission, our W20D and W22D front engine diesel platforms do not sacrifice power and performance in order to achieve better fuel economy.

“These platforms have incredible grade ability and pulling power. Our proprietary RV consumer research indicated that class A potential buyers still want power and performance — but they are also demanding better fuel economy and that is what the new W-Series delivers. Our strategy is to continue to integrate MaxxForce engines into Workhorse products where applicable, creating synergies with (parent company) Navistar(International Corp.)  along with true market differentiation.”

Quietest diesel V8

Drivers will also immediately notice that MaxxForce 7 is quiet. The noise level measured at 68.9 dBA in a low idle test. A high-pressure common rail fuel system, piezo actuated fuel injectors and a block and head design with a single-piece nodular iron bedplate are among the features that contribute to reduced noise and vibrations, a key to the MaxxForce 7’s front-engine application.

 Selling well

Presently, the Serrano coach from Four Winds International exclusively uses the W20D for both its 31Z single-slide out and 31V double slide out models. Four Winds Director of Marketing Jon Krider said dealerships with the product find that “it retails quite quickly. They’re seeing consumers that traditionally look at diesel pushers and longer coaches. These customers are finding many features with the coach and chassis that they like, starting with things like storage and the whole aerodynamic look and contemporary feel of the coach. So instead of spending $200,000 to $300,000 for a bigger coach, they can get a lot of what they want at a much lower price point.”

Regarding the W20D and Serrano matchup, Krider said, “Retail customers comment on how quiet the cockpit is for having a diesel engine right under their feet. We get a lot of comments about just how well the coach drives because of the 50-degree turning radius and being able to turn a short coach around in a tight area. And we get many good comments about the overall stability of the coach moving down the road.”

For such reasons, Krider believes spring sales of the Serrano will be even better.

High performance technology

The series sequential EVRT turbocharger provides exceptional response over a wide range of engine speeds for impressive acceleration, grade climbing, towing capability and high altitude performance. The turbo is tuned to improve fuel economy while also making the vehicle very responsive to the driver. The MaxxForce 7 also provides unaided cold-starting performance from -20° F within four seconds. Routine maintenance is economical, with oil changes every 10,000 miles.

Workhorse is an affiliate of Navistar International Corp. 

For additional information about Workhorse, call (877) 294-6773 or visit www.workhorse.com.