Could Paccar build a 15-litre truck diesel?

Is it possible that Paccar Inc. will develop a 15-litre heavy-duty truck diesel engine for the North American market, one that can match Cummins' ISX15?

The question is relevant because Paccar, like Daimler North American Trucks and Volvo Truck, have been marginally increasing their market share of Class 8 trucks at the expense of Navistar International.

With both Daimler and Volvo having the potential to offer customers diesel engines up to 600 bhp and beyond, it is conceivable that Paccar would like to be 'up with the giants' also.

In 2014, Daimler North American Trucks had a 35.8 per cent share of the North American Class 8 truck market, followed by Paccar (Kenworth Trucks had a 14.1 per cent share and Peterbilt Motors a similar 13.5 per cent) giving a total of 27.6 per cent.

With Volvo Trucks sitting at 12.0 per cent and Mack Trucks at 8.9 per cent this gave that group a total of 20.9 per cent. Navistar International enjoyed a 14.1 per cent, leaving Daimler’s Western Star with 1.7 per cent.
As to engine makers' market shares, the latest 2015 figures show that Cummins held 35.9 per cent (down from 38.4 per cent in 2014); Daimler on 30.0 per cent (27.5 per cent in 2014); Volvo with 19.1 per cent (as opposed to 18.6 per cent in 2014); Paccar with 10.8 per cent (10.2 per cent) and finally Navistar International with 4.3 per cent (5.3 per cent in 2014).

                                Increased gross train weights

There is talk that higher engine powers may be required in North America in the wake of growing pressure for US Federal gross train weights of articulated Class 8 rigs to be raised to 91,000lb, compared with the current limit of 80,000lb.

On the other hand, there is other talk too, that North American Class 8 truck users are not “power hungry”; they just like their engines to be big. One excuse for more powerful engines lies in longevity. As operators tend to keep their trucks longer than their counterparts in Europe, it is argued that a 15-litre diesel could offer greater durability (a longer life) than a 13-litre engine operating the same duties.

To meet higher power requests, Daimler has its Detroit Diesel DD16 of 15.6-litres which can develop between 475bhp and 600bhp. In Europe, where higher powers are more desirable, Volvo can put forward its D16 engine with an output of 750bhp. Scania, by the same token, can offer a V8 truck diesel able to give 730bhp.

But Paccar has no 15-litre engine; at present it has to take in the ISX15 engines from Cummins.

Cummins Inc. on the other hand does: it has the ISX15. Cummins – “the industry's favourite engine builder" – offers this six-cylinder turbocharged engine in two modes: in the peak power category of 485bhp to 605bhp (362kW to 451kW) for high pulling powers and as a fuel economy version of 400bhp to 500bhp. The high horsepower version suggests Cummins has something in reserve for future requirement growth.

But again, the US’s second largest Class 8 truck builder has no 15-litre engine. Agreed the Bellevue, Washington based truck builder takes its 11-litre MX11 and 13-litrte MX13 engines from Daf in Eindhoven, The Netherlands, to power its Kenworth and Peterbilt nameplate trucks. But it has no engine capable of giving 600bhp and over.

                              Vertical integration is in vogue

The top rating for the MX13 is 510bhp, although in the past the company’s engineers have tried to encourage more from the same engine – even to the point of touching 540bhp. But this is stretching things too far.

Cummins Inc., for all its muscle and links with Navistar International, has seen its market share shrink this past year as vertical integration takes hold in both Daimler and Volvo. And, one suspects, Cummins will see share will continue to slide.

However, the question for Paccar is straightforward: Can a financial justification be made for developing a new engine for what would be (compared with Cummins’ output) a relatively small annual volume?

This is probably the question that will have been raised in the boardroom in of Paccar Inc. more than once. The first investment could be significant. The bean counters will have a good idea for of the numbers involved.

Much depends on volumes. But there is probably not much change from at the very least $200 million to develop a new engine, with possibly more required for investment in machine tools and vehicle homologation, depending how much Paccar has already committed to its Columbus, Mississippi engine manufacturing facility.

Would it be worth rolling the dice out to buy back market share from Cummins?

Paccar executives will have watched with more than passing interest as majors like Daimler and Volvo intensify their efforts in vertical integration. Should Paccar do the same?

                                     Global technology leader

And where would design of the 15- or 16-litre engine be conducted? Paccar has no North American experience of designing and developing heavy-duty truck diesel engines even though Paccar describes itself a global technology leader which designs and manufactures "advanced diesel engines" for use in light-, medium- and heavy- duty applications.

To fully justify this description one might expect that Paccar Engine Company would need to have a range that extended to 15-litres, or even beyond

In recent years, Paccar has relied heavily for its powertrain technology on European know-how from Daf in Eindhoven, the company it acquired to enter the diesel engine business.

Before the arrival of Daf, Paccar relied on the diesel offerings of Caterpillar, Cummins and Detroit Diesel. But times have changed. Caterpillar quit making on-highway diesels while Detroit Diesel fell under the spell of Daimler AG. Only Cummins remains, as at one time Mack also built its own engines.

Daf does however use some Cummins diesel engines but only for its lighter XF and CF trucks built in Europe. In the main Cummins sources these needs for its six-cylinder engines from its engine plant in Darlington, UK. Other diesel engines, like its four-cylinder models, are sourced from Cummins’ joint venture business in China.

                         Is something happening in a quiet corner?

Some might have thought when Paccar acquired Daf, that the Bellevue-based company would out-source all its engines. Had that happened, Cummins executives would not have been able to believe their luck. But it didn't and now there is the prospect of a third engine family at Paccar.

Agreed, creating a diesel in the size range of 15-litre to 16-litres is a tall order, but it could nevertheless be happening in some quiet corner of a forward project office in Eindhoven. Even single cylinder trials could have been under way for some time.

Dutch engineers, never keen to stand still for long, would relish the opportunity to have a go at designing and building a "big one".

They would, if they have not already done so, pitch their engine at the top end of Cummins' range, namely in the peak power band of 600 bhp plus, but with some power in reserve for future growth.

It is conceivable, when manufacturing, engineering and product planning experts at Paccar put together their proposals for their new $400 million engine manufacturing plant in Columbus, Mississippi, they looked to the future and inked in the capability of building larger engines in future. They would be silly not to do have done so.

It will be interesting to see what happens in future and, if the MX15 emerges, what materials will it use for critical components. The MX11 and MX13 engines use compacted graphite iron (CGI) for cylinder block construction. It might be reasonable to suppose that if there is an MX15, it too will have a CGI block, and even a CGI head as well.