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On the Paccar Twins' Engine

A year ago we predicted that the new Paccar 12.9-liter MX engine used in Europe would be seen here in North America. So it was hardly a big surprise to see the engine in a Peterbilt 389 and a Kenworth T660 at a Dallas truck show in the fall. The MX was incredibly quiet and had plenty of get up and go.

by Steve Sturgess, executive editor
January 1, 2008
On the Paccar Twins' Engine

 

4 min to read


A year ago we predicted that the new Paccar 12.9-liter MX engine used in Europe would be seen here in North America. So it was hardly a big surprise to see the engine in a Peterbilt 389 and a Kenworth T660 at a Dallas truck show in the fall.

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I hadn't noticed at the time, but on a recent trip to DAF in The Netherlands, I realized that the MX engine features, among other interesting things, two-stage turbocharging.

DAF is owned by Paccar and is one of Europe's most popular brands, in many cases topping the various national charts with its smaller LF, its regional heavy-duty CF or its skyscraper-like, long-haul Space Cab XF cabovers.

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The top-of-the-line XF was voted the International Truck of the Year 2007 by the panel of European editors who give out the annual trucking award.

The smaller truck, the LF, was Truck of the Year in 2002. We are just getting the medium-duty LF over here as the Peterbilt 210/220 and Kenworth K360 low cabovers. (They are becoming available in Europe as hybrids. But that is another story.)

The big-news MX engine currently is available in both the CF and the XF. In the big XF105, the 12.9-liter MX is available in three ratings, with the top at 510 horsepower and 1,850 pounds-feet of torque - pretty good numbers for a 13-liter.

I had an opportunity to drive a Super Space Cab XF105 - in fact, several different XF and CF models - in a brief afternoon at the Dutch test track. The engine was impressive, being incredibly quiet and smooth and having plenty of get up and go - so much so that the big XF cab would rock and roll on its soft suspension during acceleration off the line.

The MX engines were mostly matched with fully automated ZF AS-Tronic transmissions (mechanically the same as the Meritor FreedomLine available here). Together, they made it easy to pour on the coals and get the trucks smartly up to speed, despite being loaded up to Europe's maximum 44 tonnes (97,000 pounds). It was a fun afternoon, part of a visit that included tours of both the truck assembly operation in Eindhoven and the huge engine R&D labs.

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The MX debuted at the Hanover, Germany, truck show in 2004 and has been largely responsible for the DAF success story, at least as far as the heavy-duty trucks are concerned. This was very apparent while touring the truck plant and seeing the flat-out production of the CF and XF models. Sharing the same enormous plant site is the newly expanded - from 14 to 34 test cells - Paccar engine laboratory. As we toured, we were shepherded into a display area where we found a Kenworth and a Peterbilt, both with an MX engine.

This laboratory is equipped with state-of-the-art emissions facilities as well as the usual durability and development capabilities. It is where the engines are being developed to meet the EPA 2010 emissions regulations, as well as Euro 6, which is due to hit over there in 2012.

There were some guarded comments about the final configuration of the engines for North America, but we'll make another prediction: Series turbocharging will be a part of the air handling for the our versions of the MX. And while little was said of the timing or the master plan, the already well-proven 12.9-liter MX will likely be the base engines for Peterbilt and Kenworth starting in 2010.

The engine is an in-line six with in-block camshaft. It has unit pump injection, and the timing gears are located at the back of the engine. The high-pressure fuel injection system was developed in association with Delphi. The overhead and compression brake were designed and developed by Jacobs. So the engine already has strong ties to North America.

While much of the North American MX engine development is being done in the Netherlands at this impressive laboratory facility, they will be assembled in the U.S., in a new $400 million engine plant already under construction in Columbus, Miss.

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It'll be in-house competition for Caterpillar and Cummins, but the MX engines look darned good.

I say "bring 'em on."

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