There is a piece in Forbes magazine, provided by Associated Press, an organisation that gets rather upset if its content is used elsewhere, so forgive us if we don't provide a link. Google Cummins instead, click on the news tab  and you'll get there, but please don't say we sent you, otherwise there might be unpleasantness.

Anyway, one analyst suggests that the move is something of an admission that Cummins' technology choice for the 2010 emissions standards needs to be modified. We'd opine that moving from EGR to SCR is something of a modification; a complete about turn would seem to be a more appropriate choice of phrase here. However, the same analyst also makes the extremely fair point that earnings growth after 2010 in the heavy duty on-highway sector could well disappoint. We'd agree entirely; in fact, we' go further and suggest that, if SCR is taken on-board as the global standard for emissions control, then we can see very little difference between the situation confronted by CAT earlier this year, and that now faced by Cummins. In a verticalised, scale-driven truck manufacturing industry, why outsource an engine? Will Cummins be with us in this sector in three years' time? We don't know, but we wouldn't be surprised to see them retain their focus on medium duty product, and exit the HD market.

We're a bit confused by the view of the other analyst quoted in the report. He suggests that this move is positive for Cummins, and that it will benefit the company through increased content per vehicle post 2010.

This we cannot see. Cummins will doubtless get Paccar's 15 litre business post 2010, and, in a somewhat ironic twist, is already signed up as International's supplier of the same. Will either Paccar or Navistar be likely to tout Cummins over their own product? We suppose they could, but it would be damn nice of them so to do. And if, as seems possible, the US moves towards 13 litres as a default choice, the ISX begins to look a bit spare. With Navistar, we could of course point to the fact that there may well be some irritation reference Cummins' defection from the SCR camp, but, once again, we'll assert that, as MAN is using the same engine - D20 / D26 - for more or less the same emissions level - Euro VI - and has opted to apply SCR to the back end, we reckon that there's a better than good chance that International HD trucks will be queuing up for DEF refills in 2010.

This leaves us with Daimler Trucks North America and Volvo. We assume that both opted to retain Cummins as an engine choice on the basis that SCR might well crash and burn in North America. UBS, 81 per cent of operators don't want it - see here.

But now SCR has no competitor in the 15 litre segment, we can suggest that this hedged position is no longer necessary. Both marques have their own 13 and 15 litre engines, both are known brands to North American operators, and both, we would assume, are going to get very cute in terms of what they offer to buyers in terms of warranty. In sum, no obvious space for Cummins here either.

So, farewell HD Business? On balance, probably.