Van, Truck, Trailer, Bus and Coach Aftermarket News in Ireland

Life in the Euro Zone: Euro-5 Vs Euro-6

The switchback of registration figures for the truck industry follows a graph that can easily be overlain by another: the advent of new emissions legislation, and the severity of the engineering involved. SMMT Chief Executive Mike Hawes has reported the fourth consecutive monthly fall in truck registrations, and the prime suspect is the buy-forward of Euro-5 chassis that led to some startling figures late last year.

Some of the earlier Euro emission levels had a relatively small impact on costs for truck manufacturing, but moving from Euro-5 to Euro-6 has been one of the most costly, adding a ball park €10,000 to a typical tractor list price. Why?


Up to and including Euro-5, heavy-duty diesels had largely opted for one of two after-treatment technologies, namely SCR (selective catalytic reduction using AdBlue) or EGR (exhaust gas recirculation). The specs of Euro-6 rendered truck manufacturer’s competing Euro-5 marketing campaigns redundant, as the new lower emissions needed both technologies to help them limbo down. There are two SCR-only exceptions to this, the first being a 13 litre, 410hp unit from Scania. The second is much more significant, Iveco has avoided the use of EGR on its entire engine line-up. Martin Flach, Iveco’s UK Technical Director says the rationale was to keep things simple. “It’s all about avoiding complexity wherever possible, and we have been working on SCR systems for seven years, it’s not new,” he explained, adding: “As soon as we knew we could refine the dosing system with a much finer spray of urea solution, and attain Euro-6 without pushing acidic exhaust gas through the engine for a second trip, we knew it was the best method.”

It may well have been the best method, but it hasn’t been cheap. The cost of refining Iveco’s patented Hi-eSCR (high-efficiency selective catalytic reduction) has been significant. All manufacturers have also had to add a vast array of extra sensors to monitor their engine’s continued cleanliness, and many have also conducted comprehensive re-packaging exercises on their chassis, to accommodate bulky metalwork. Countering accusations of high AdBlue consumption for his engine range, Iveco’s Flach is unapologetic. “The cost implications of extra Adblue are trivial, and infinitely preferable to higher diesel use,” he says. Vindication with gravitas comes from Ricardo’s Andrew Nichol. Speaking at the IRTE conference last year, he agreed that questions over long-term reliability would lead most manufacturers to refine their systems in the years ahead to minimise the use of EGR, with the goal of ultimately taking it out of the equation entirely.

The most obvious addition to the truck chassis at Euro-6 is the DPF (diesel particulate filter), and many fleet engineers have been concerned that it could represent a maintenance time bomb for them. With OBD (on board diagnostics) constantly policing compliance it is true that there will be no avoiding their maintenance. Lurid tales of trucks being stopped dead in their tracks for want of a clean filter are wide of the mark. It will be a predictable event with many alerts to trigger the workshop. However, the mileages that can be achieved before a DPF clean is needed with vary widely. Most influential will be duty cycle. In practice, DPFs are most likely to be cleaned on a service exchange unit (SES) basis to avoid the downtime penalty of the day and a half that it is expected to take. As Euro-6 gets established, large fleets could invest in the cleaning equipment themselves, and have a few spare filters on standby, but truck manufacturers recommend this to be handled by specialists, usually the DPF makers themselves. An SES approach will reduce the  issue to a just another planned maintenance job.

How much lower?

DAF’s Chief Engineer, Ron Borsboom, describes the firm’s drivetrain development engineers as, “World champions at measuring almost nothing.” It’s a tongue-in-cheek reference to the incredibly low emissions levels that Euro-6 mandates. Nick Blake, Head of Engineering at Mercedes-Benz Trucks in the UK agrees, and he points out that a heavy tractor emits less pollutants from its exhaust than it does in the form of dust from friction materials and worn tyres.

With the earlier Euro levels, there was a resigned expectation that successively tougher measures would follow at regular intervals. With Euro-6, the mood has changed as many feel that there is very little that can be done to reduce emission levels further. DAF’s UK Managing Director, Ray Ashworth, says there are other considerations. He commented, “I had harboured hopes, in a market driven by legislation, and without a Euro-7 on the horizon, that the industry might now be able to settle down and put some energy into creative solutions that will push operating economy forward; to do something different.” But, he says, “With the EU now coming up with potential cab dimension changes that could precipitate a redesign, I do wonder if that energy is now going to be spent elsewhere.”

The journey from Euro-1 to Euro-6 has cost billions of Euros and it’s brought us truly clean trucks. But with the engineering complexity has come better reliability too. While the tide is still flowing away from operators’ own workshops, and towards R&M contracts with franchised dealers, there are still some for whom maintaining a Euro-6 fleet holds no terrors.