Feature March 1, 2012 by
Jim Anderton, Technical Editor
Where are the Diesels?
I’ve said it before and I’ll say it again: Where are the diesels? Yes, Volkswagen has built a tidy niche market with compression ignition engines, especially the Jetta, and Mercedes also has a diesel history. But for mainstream...
I’ve said it before and I’ll say it again: Where are the diesels? Yes, Volkswagen has built a tidy niche market with compression ignition engines, especially the Jetta, and Mercedes also has a diesel history. But for mainstream manufacturers in North America, diesel is only for massive full size pickups. It’s great that a Silverado dually can tow a D9 Cat, and it’s cool that you can order a Dodge Ram with an engine that belongs in a dump truck, but what about the rest of us?
Years ago I attended an Alberta press event for the launch of the then new GM diesel pickup line. It was most impressive, with power beyond anything even a building contractor could possibly need, along with speed and relatively good fuel economy for large, dually pickups. Technology was, and is, excellent, but I couldn’t help thinking, why not saw the engine in half? A four cylinder diesel, maybe 3.0 L or 3.5 L, with a small diameter turbo, and it should be possible to power a half ton with plenty of towing power for most uses and adequate speed with great fuel economy. It could even be cheaply developed. Readers of a “certain age” might remember that International Harvester’s little Scout SUV had a four cylinder that was simply one bank of the V-8, and Pontiac even earlier sawed their 389 in half to make a four for the then-new Tempest.
The advantages are considerable. A half V-8 could be machined and assembled on the same transfer lines and assembly plants as the V-8s. Much of the engine dress and accessories could be common. Engine and transmission mountings could be very similar too, and pickups are still easy to package with adequate under hood space and rear-wheel drive. The main reason engineers and marketing people give for the lack of diesels in light duty vehicles? “There’s no demand,” they say, claiming that people don’t want the inconvenience of finding fuel in urban areas and that they won’t pay the additional cost. For a 2L subcompact, this makes sense, but the fuel savings, longevity and higher residual value of a “big four” turbo-diesel half-ton might make it a popular choice.
Everywhere else in the world, small diesel pickups are the norm. I’ve met African techs who have never worked on a gasoline engine in their lives. And with direct-injection gasoline technology going forward, there should be less of a cost premium to building diesel engines. There are lots of Asian Class 4 trucks on our streets now with small, efficient diesel engines. Why not for light trucks? No market? I think it’s there for the picking.