I've been digging for info on NG vehicles for 2 or 3 months probably. I'm no expert and I don't have any "inside" knowledge. I'm just a guy turning over rocks and when I come across something interesting I will share it on this board. I don't work in the trucking industry so I must admit I was a little surprised at how long some of these NG engines have been in service. I think the Westport engines go back to early this decade (02 or 03 maybe). As for the question about Cummins and Freightliner; I think Freightliners are available with Cummins diesels but the majority of their trucks are equipped with either Mercedes or Detroit diesels. As far as I know neither Mercedes or Detroit is offering an NG engine at this time. Thus the agreement with Cummins/Westport. In addition to Freightliner, Diamler also marketed trucks under the Sterling brand which was also available with Cummins/Westport power. They are discontinuing the Sterling brand.